Point-to-Point (PtP) wireless networking refers to a wireless link connecting two fixed locations directly to each other, creating a dedicated communications pathway. In a typical PtP setup, two network devices (often called wireless bridges or radios) with directional antennas are aligned so they can exchange data over radio waves, effectively replacing a physical cable between the sites. This creates a **secure, reliable link** to share data, voice, video, or network traffic between the two sites **without needing any wired connection**. Each end of the link usually consists of a transceiver (radio) and antenna; one side transmits and the other receives (and often both ends do both). Because the link is exclusively between these two endpoints, the full wireless bandwidth is available to that connection alone, and the communication can be tightly focused and high-performance.

**How PtP Wireless Links Work:** A PtP wireless link works by establishing a direct wireless bridge between the two endpoints. Each endpoint’s radio is connected to the local network (e.g. via Ethernet to a switch/router) and configured to communicate only with its counterpart. The radios use highly directional antennas (such as parabolic dishes or focused panels) pointed at each other to concentrate the signal. This directional focus helps achieve longer distances and higher signal quality by sending most of the radio energy toward the intended receiver. Once aligned and configured, the two radios form a transparent link – data sent into one end emerges out the other end as if the two networks were directly wired. In essence, the wireless bridge **creates a single network segment or extension between the two sites**, allowing devices on either side to communicate as if on the same local network. Because the connection is point-to-point, **latency can be very low and throughput high**, approaching wired speeds in many cases.

PtP wireless links can span **from very short distances (within one building or campus)** to **many kilometres apart**, depending on the technology and antennas used. Modern point-to-point bridges can reliably connect sites **several miles apart** – often **10–15 miles (≈16–24 km)** or more in clear conditions. For example, a PtP bridge might be used to link an office with a remote warehouse across town, two buildings on a campus, or a security camera on a pole back to a control room, all without running fibre or copper cables. The focused, dedicated nature of PtP links also means they are **resistant to interference** compared to general Wi-Fi – the narrow beam and exclusive link reduce the chance of other devices disrupting the signal.

Not all point-to-point wireless links use the same technology or radio frequency. Various **frequency bands** and wireless technologies are employed for PtP networking, each with its own characteristics. These include traditional unlicensed Wi-Fi bands, newer millimetre-wave frequencies, and regulated licensed bands. The choice of band impacts the link’s range, capacity, and requirements. Below is a breakdown of key PtP technologies and bands:

- **Unlicensed Bands (2.4 GHz & 5 GHz ISM)** – Many PtP links use unlicensed spectrum such as the 2.4 GHz or 5 GHz bands (commonly used by Wi-Fi). Equipment operating here (often based on Wi-Fi standards like 802.11ac/ax) is inexpensive and easy to deploy without special permits. **5 GHz** is popular for outdoor bridges because it can carry high data rates with relatively low noise in rural areas. It provides faster speeds over shorter distances, whereas **2.4 GHz** can cover longer distances or slightly better penetrate obstacles (at the cost of lower throughput). In practice, 5 GHz links are used for many short-to-moderate range links (up to a few miles) where moderate throughput (hundreds of Mbps) is needed, and 2.4 GHz might be used if 5 GHz is too congested or for a bit more range at lower speeds. Because these bands are unlicensed, anyone can use them – which means **no licensing fees** but also a higher risk of **interference** from other users of the band (neighbouring Wi-Fi networks, etc.).

- **Millimetre-Wave Bands (60 GHz V-Band)** – The 60 GHz band is an unlicensed **mmWave** frequency (often called V-Band) used by newer point-to-point devices. **60 GHz links can deliver very high throughput (gigabit-speed)** thanks to the large bandwidth available. They are ideal for short-range links (typically under 1–2 km) because signals at 60 GHz are heavily attenuated by the atmosphere (especially oxygen absorption). This **oxygen absorption (~16 dB/km) limits the range** of 60 GHz, effectively confining the signal to a short distance. While this limits coverage, it has the benefit of **natural security and interference resistance** – a 60 GHz beam tends to drop off quickly and will not interfere with or be intercepted by other systems far away. 60 GHz PtP links (such as **802.11ad/ay based products**) are often used for **“wireless fibre” applications**, like connecting two buildings in a campus or providing fibre-like speeds across a street. They require precise alignment due to very narrow beam widths (a 60 GHz link with a 1-foot antenna has a beam around 4–5° versus over 100° at 2.4 GHz. 60 GHz is unlicensed in many regions, so deployment is fast and low-cost, but rain fade (signal loss in heavy rain) must be accounted for on longer 60 GHz links.

- **Millimetre-Wave E-Band (70/80 GHz)** – The 71–76 GHz and 81–86 GHz bands (often paired for full-duplex) are known as **E-Band**. These are usually **“lightly licensed”** in many countries – meaning you must register the link and obtain a license, but the process is simpler and cheaper than traditional microwave bands. E-band supports multi-gigabit data rates (even 10 Gbps full-duplex on high-end gear) and can reach a few kilometres. Because these links operate at very high frequency, they use highly directional antennas (often small dishes) and have **line-of-sight** requirements. **Interference is nearly zero** due to narrow beams and exclusive licensing – **80 GHz links are essentially interference-free**, giving fibre-like performance. The trade-off is the need for careful alignment and the fact that rain can significantly affect range (higher frequencies suffer greater rain attenuation). E-band is popular for **high-capacity enterprise or ISP backhaul** links in urban areas, where one can quickly get a licensed gigabit link without running fibre. (Licensing typically involves an online registration to ensure no frequency conflict with existing links, with approvals often instantaneous.)

- **Licensed Microwave Bands (6–38 GHz)** – Traditional microwave PtP links operate in lower microwave bands like 6, 11, 18, 23, or 38 GHz, which **require a radio license** from the regulator. In exchange for licensing fees and coordination, the user gets an **exclusive frequency channel** in a given area, virtually eliminating interference from other systems. Common licensed PtP bands include 6–23 GHz for long-distance links (these frequencies propagate farther and handle rain better than mmWave) and 28/38 GHz for shorter high-capacity links. Telecom carriers and ISPs frequently use licensed microwave for reliable backbone connections. For example, licensed 11 GHz or 18 GHz links might connect cellular towers or provide rural broadband backhaul. The **benefit of licensed PtP** is consistency and reliability – since no one else can transmit on your frequency in your area, the link can operate at full performance without contention. However, equipment costs are higher and one must obtain and periodically renew the license (often 5–10 year terms). Licensed microwave radios often use proprietary microwave modem technology (not Wi-Fi based) and can achieve **carrier-grade availability (99.999% uptime)** with proper design (including adaptive modulation, larger antennas, etc.).

- **Sub-1 GHz Bands (900 MHz, etc.)** – In some specialized cases, PtP links use frequencies below 1 GHz, such as **900 MHz ISM** (unlicensed in some regions) or TV White Space. These frequencies travel farther and penetrate obstacles better at the cost of very limited data rates (generally tens of Mbps). They are useful for non-line-of-sight scenarios or extremely long links where only minimal bandwidth is needed. For instance, in a heavily wooded area, a 900 MHz wireless link might be the only way to connect a remote sensor or gate control, as it can penetrate foliage where higher frequencies fail. Due to narrow available spectrum, these are not used for high-throughput needs, but rather for reaching places other links can’t (or as backup links).

**Licensed vs Unlicensed Spectrum:** A major distinction in PtP technology is whether the link’s frequency is *unlicensed (license-exempt)* or *licensed*. Unlicensed bands (2.4, 5, 60 GHz, etc.) allow quick deployment by anyone but are open to **crowded use and interference**, requiring good channel planning. Licensed bands (e.g. licensed microwave or E-band) give exclusive use of a frequency in an area, yielding **predictable performance with no interference** at the cost of coordination and fees. We will compare these in detail in a table below.

Not all point-to-point links are equal – some are just a few meters across a room, while others stretch for kilometres between mountaintops. The deployment environment (indoor vs. outdoor) and distance greatly affect how a PtP link is designed and what equipment is suitable. Here are key differences between **short-range or indoor PtP bridging** and **long-range outdoor PtP links**:

- **Range and Environment:** **Short-range indoor links** might span a single large room, between floors of a building, or across a campus courtyard – typically distances from a few meters to a few hundred meters. **Long-range outdoor links** can reach multiple kilometres, often linking different buildings or sites across towns or rural areas. Indoor links are usually in controlled environments (no wind, minimal weather issues), whereas outdoor links must contend with weather, temperature extremes, and terrain.

- **Frequency Choice:** Indoor and very short links can leverage higher frequency bands for maximum speed, since range is limited. For example, a 60 GHz wireless bridge kit can be used **between two buildings on the same campus** to get multi-gigabit throughput over a short distance. Outdoor long-range links often rely on lower frequencies (like 5 GHz or licensed 6–11 GHz) which propagate farther with less signal loss. High-frequency mmWave links (60/80 GHz) outdoors are generally kept to shorter distances (sub-2 km for 60 GHz, maybe 3–5 km for 80 GHz in good weather) to maintain reliability. So, **short indoor = high freq OK; long outdoor = lower freq needed** in many cases.

- **Line-of-Sight Requirements:** Generally, **direct line-of-sight (LOS)** is important for all true PtP bridges. However, indoors you might get away with very short links even if there are walls or reflections (for instance, a 5 GHz link across a open warehouse might tolerate some obstructions at short range). For long outdoor links, clear LOS is almost always mandatory – even a small tree or building in the path can disrupt the connection. Outdoor PtP planning often includes a **Fresnel zone clearance** check (ensuring no obstacles encroach on the radio beam path). Indoor links may have more multipath (signals bouncing off walls), while outdoor links are usually engineered to avoid multipath by having clear LOS or using antenna polarization and spacing techniques to mitigate it.

- **Antennas and Equipment:** Short-range or indoor bridges often use compact hardware with integrated antennas. For example, a simple **wireless bridge kit for indoor use** might look like two small boxes or panels that you point roughly at each other. They might have moderate-gain antennas since distance is low. In contrast, long-range outdoor links frequently use large, high-gain directional antennas – e.g. 2-foot or 3-foot diameter parabolic dishes – to focus the signal tightly and achieve long distances. The outdoor units must be rugged and weatherproof, typically rated for **outdoor installation (weatherproof enclosures)** to handle rain, wind, and sun. Mounting hardware is also more substantial outdoors (steel brackets on poles or towers vs. simple wall mounts indoors).

- **Throughput and Bandwidth:** Short indoor links, especially using newer technology (like 60 GHz or Wi-Fi 6/6E bridges), can offer extremely high throughput (1–10 Gbps) because the distance is short and high-frequency channels can be used. Long outdoor links might be more constrained by distance and regulations – for instance, a 10 km link using 5 GHz might only sustain a few hundred Mbps due to power limits and lower signal-to-noise at that range. Licensed long links can still achieve high throughputs, but often design for reliability (lower modulation for rain fades, etc.). In essence, **short links can be over-engineered for speed, long links are often engineered for reliability over speed**.

- **Interference Considerations:** Indoor environments might have a lot of other Wi-Fi devices, so an indoor PtP could face interference from nearby Wi-Fi APs (if using 2.4/5 GHz). However, since distances are short, you can often use the maximum channel width and power allowed to blast through. Outdoor long links, if unlicensed, may suffer from other radios in the area (especially 5 GHz is commonly used by many). The risk of interference grows with distance because the antennas may pick up distant transmitters if not perfectly aligned. Licensed outdoor links avoid this by exclusive channels. Also, outdoor links have to contend with **noise floor** in open environments, whereas indoor links are somewhat isolated inside buildings.

- **Installation and Alignment:** Setting up an indoor bridge can be straightforward – devices might auto-align if close, or a quick eyeball alignment might suffice for short range. Long outdoor links require careful alignment using tools (fine-tuning antenna pointing often with live signal metrics) because a tiny misalignment can cause a big signal drop over kilometres. Outdoor installs also involve considerations like tower or rooftop mounting, grounding for lightning protection, and running Power-over-Ethernet cables outdoors. Indoor links are typically plug-and-play and can even be temporary, while outdoor ones are more permanent installations with proper mounting and lightning arrestors, etc.

In summary, **indoor/short PtP links** prioritize high speed and ease, often using unlicensed bands and smaller gear, suitable for bridging network gaps within or between buildings on a campus. **Outdoor/long PtP links** prioritize distance and reliability, using higher power and gain, sometimes licensed spectrum, and robust hardware to maintain a stable connection across challenging distances and conditions.

Point-to-point wireless bridges are employed across many industries to solve networking challenges where wired links are impractical or too costly. Here we break down some **common use cases** and scenarios for PtP links:

**Security integrators** often use PtP wireless links to connect cameras, alarms, and access control devices in situations where running cable is difficult. For example, a set of IP surveillance cameras on a light pole in a parking lot can use a wireless bridge to send video back to the main building. PtP links for CCTV provide a reliable, low-latency connection needed for streaming video. They are particularly useful for covering remote or hard-to-wire spots like gate entrances, perimeter fences, or distant buildings on a facility. Instead of trenching fibre or coax out to each camera location, a wireless bridge can beam the footage across the site.

These security-focused links are typically short to medium range (hundreds of meters to a few kilometres at most), and often use unlicensed bands for quick deployment. **5 GHz PtP bridges** are popular in this space – they can easily handle the bandwidth of multiple HD cameras (tens to a few hundred Mbps) and are cost-effective. For instance, a 5 GHz outdoor wireless bridge kit might offer ~150 Mbps throughput up to 8 miles (≈13 km) line-of-sight, which is sufficient for a cluster of CCTV cameras. Brands like Ubiquiti and Mikrotik are commonly used by security installers for such links, offering products (e.g. Ubiquiti **NanoBeam** or **PowerBeam** series) that mount near the camera and shoot back to a receiver on the main building. In urban surveillance (city-wide CCTV deployments), more robust **licensed links** (or 60/80 GHz for high capacity) may be used to bring feeds from multiple camera hubs to a central control room. For example, Siklu’s mmWave radios have been used in city surveillance networks to deliver gigabit capacity from camera aggregators. The key requirements in this use case are **reliability (for always-on security)** and sufficient bandwidth for video, all while keeping costs reasonable – PtP wireless often meets these needs better than pulling dedicated cables across long distances.

Internet Service Providers, especially **Wireless ISPs (WISPs)**, heavily rely on point-to-point wireless links for backhaul. In areas where fibre is unavailable or too expensive to deploy (common in rural regions), PtP wireless is used to connect remote sites to the internet backbone. For example, a WISP might have a main tower connected to fibre in a town, and then use PtP links to reach other relay towers or communities over many kilometres. These links serve as the **backhaul**, carrying aggregated internet traffic. High throughput and reliability are crucial here, as these are the lifelines feeding many customers.

Both unlicensed and licensed technologies are used in ISP backhauls. Many WISPs start with unlicensed 5 GHz links (due to low cost and no license needed). As they grow or face interference, they may move to licensed microwave bands (11 GHz, 23 GHz, etc.) to guarantee cleaner spectrum. For long rural spans, lower frequencies like 6 GHz (licensed) might be used because they can go further with less attenuation. ISPs also increasingly use **80 GHz E-band links** for major backhauls since those can deliver fibre-like speeds (1–10 Gbps) to a tower, albeit typically within shorter range (a few km). An ISP backhaul deployment might involve a chain of multiple PtP hops linking a remote village to the nearest city. Each hop needs proper alignment, often mounted on tall masts or grain silos to achieve line-of-sight across hills and trees.

The **rural connectivity** use case often encounters challenging terrain – so PtP links are designed with high fade margins (to handle rain or snow), and sometimes multiple links for redundancy. Companies like Cambium Networks and Mimosa (Airspan) design PtP radios specifically for WISP backhaul, supporting features like Adaptive Modulation (which lowers throughput gracefully during heavy rain to maintain link uptime) and GPS sync (to coordinate multiple links and minimize self-interference in crowded tower setups). For example, Cambium’s **PTP 820** and **PTP 850** series are carrier-grade licensed microwave units used by ISPs for long-haul links, while their **PTP 550** (5 GHz, unlicensed) can bond channels for ~1 Gbps throughput on shorter links. WISPs choose technology based on a trade-off: **unlicensed = lower cost, quick deploy but interference risk; licensed = higher reliability but with licensing overhead**. In areas with a lot of wireless congestion, WISPs often secure licensed spectrum to ensure their backhaul is stable. Rural point-to-point links have been a game-changer in bringing broadband to remote areas that would otherwise wait years for wired infrastructure.

Enterprises and campus networks use point-to-point wireless to extend their LAN between buildings or sites. A classic scenario is an organization with two office buildings across the street or a few kilometres apart – running fibre may be impractical or time-consuming (perhaps involving permits to dig up a road), so a PtP wireless bridge is deployed instead. This provides a **private data link** between the buildings, effectively creating one network. Enterprises often use this for connecting branch offices, linking to data centres, or providing backup connectivity. The capacity needs can vary: a small business might only need 100 Mbps between sites for file sharing and VoIP, whereas a large enterprise or hospital campus might need multi-gigabit throughput to handle all inter-site data and failover for internet connections.

For building-to-building links, ease of deployment and high reliability are attractive. **Unlicensed 60 GHz bridges** have become popular for enterprise campus links because they offer **Gigabit speeds and are quick to install**. For example, Ubiquiti’s **UniFi Building-to-Building Bridge (UBB)** kit uses 60 GHz for up to ~1.5 km with ~1 Gbps throughput, and falls back to 5 GHz if needed. This kind of solution is almost plug-and-play and can save leasing expensive fibre lines. Similarly, Mikrotik’s **Wireless Wire** is a 60 GHz kit that provides an out-of-the-box encrypted Gigabit link at short range (ideal for two offices across a street). Enterprises that require guaranteed uptime or higher capacities might go for **licensed links or higher-end gear**: e.g., a bank connecting two data canters 5 km apart might deploy a pair of **80 GHz radios** (like Siklu **EtherHaul** or Cambium **PTP 820E**) to get a multi-gigabit, low-latency link with an SLA. Some even use dual links (for redundancy) or a combination of fibre and wireless (wireless as a backup path in case fibre is cut, since PtP wireless is completely independent of physical cabling).

Another enterprise use is temporary links – for instance, at construction sites or disaster recovery situations, companies set up temporary PtP wireless to connect into the corporate network when wired options are unavailable. Because PtP bridges can be deployed in hours, they are an efficient solution for short-term connectivity between facilities.

Overall, enterprises value PtP wireless for **cost savings (no recurring lease), speed of deployment, and flexibility**. Modern wireless encryption and authentication features also ensure that these links can be secured for sensitive corporate data. With proper planning (spectrum choice, alignment, etc.), an enterprise PtP link can run for years as a reliable piece of the network infrastructure.

One of the key considerations in PtP wireless is whether to use licensed spectrum or unlicensed spectrum. Each approach has pros and cons in terms of range, speed, cost, and regulations. The table below compares **Licensed** vs **Unlicensed** point-to-point wireless technologies on important factors:

| Aspect | **Licensed PtP** (Exclusive Spectrum) | **Unlicensed PtP** (Shared Spectrum) |

|------------------|--------------------------------------------------------------------|-------------------------------------------------------------|

| **Spectrum Access** | Operates on a *licensed frequency band* – you pay for exclusive rights to a channel in a region. No other operator can use that frequency in your area, providing a clean spectrum. | Operates on *unlicensed bands* (e.g. 900 MHz, 2.4 GHz, 5 GHz, 60 GHz) open to anyone. Must coexist with other devices; no exclusive rights (first-come, first-served usage with etiquette rules). |

| **Coverage & Range** | Can use lower-frequency bands (e.g. 6–11 GHz) that propagate far, and higher allowed transmit powers because of coordination. Licensed links can reliably cover long distances (10+ km) if engineered well. | Range is workable (many unlicensed links cover 5–10 km), but higher-frequency unlicensed bands (e.g. 5 GHz) have stricter power limits and more interference, which can reduce practical range. Very long links in unlicensed band risk encountering other signals or hitting EIRP limits. |

| **Throughput** | Often high throughput with guaranteed availability. Many licensed PtP radios use advanced modulation and wide channels in reserved spectrum – e.g. gigabit-speed in 80 GHz or hundreds of Mbps in 11/18 GHz. Performance is consistent since there’s minimal external interference. | Can also achieve high throughput (e.g. 5 GHz 802.11ac links can exceed 500 Mbps, 60 GHz links ~1–2 Gbps). However, actual throughput may fluctuate if interference or noise is present. Top speeds often require using wider channels which might be prone to more interference in busy areas. |

| **Interference** | **Minimal interference** – exclusive channel means other radios won’t interfere (assuming everyone abides by licensing). This yields stable latency and throughput. Great for critical links that require high uptime. | **Higher interference risk** – shares spectrum with others, so performance can degrade if the band is crowded or if a neighbour sets up a competing link on the same channel. Requires careful channel selection and possibly re-tuning over time. Technologies may include adaptive noise mitigation, but there’s no legal protection from interference. |

| **Regulation & Setup** | Must obtain a license from regulator (e.g. FCC, Ofcom) before use. This involves frequency coordination, registration of link details (GPS location, antenna height, etc.), and fees (often substantial). Setup time is longer due to paperwork, and ongoing compliance is needed (renewals, interference reporting). | Generally plug-and-play within legal limits. No individual license required – just use certified equipment and adhere to rules (maximum power, use of DFS channels, etc.). Deployment is faster and simpler. Still must ensure devices are country-approved and follow any dynamic frequency selection or power limits in band. |

| **Cost** | **Higher cost** – Licensing fees add to OpEx. Equipment is typically more expensive, as it’s carrier-grade hardware. However, cost brings performance and support (often coming with SLAs, professional support from vendor). Suitable when link is mission-critical and budget allows. | **Lower cost** – No license fee. Many unlicensed PtP devices are inexpensive (leveraging mass-market Wi-Fi chipsets). You can deploy multiple links without direct fees except the hardware. Lower cost makes it ideal for budget-sensitive projects (small ISPs, CCTV links, etc.), accepting a bit more risk on reliability. |

| **Examples** | 6, 11, 18, 23 GHz microwave links for telecom backhaul; 80 GHz E-band gigabit links. Vendors: Cambium (PTP 820/850), Ceragon, Siae, Siklu (EtherHaul, licensed mode) – offering licensed radios with 99.99% uptime targets. | 2.4/5 GHz Wi-Fi bridges, 60 GHz V-Band links (license-free worldwide). Vendors: Ubiquiti (AirFiber, NanoBeam), Mikrotik (SXT, LHG, Wireless Wire), Cambium (ePMP series), Mimosa (B5/B24) for unlicensed. Quick to set up for inter-building links, camera connectivity, WISP last-mile, etc. |

**In summary**, licensed PtP links excel in **reliability and interference immunity** – they are the go-to for carrier/backbone connectivity where consistency is paramount. Unlicensed PtP links excel in **flexibility and cost-effectiveness**, perfect for rapid deployments and lighter-duty links. Many networks use a hybrid approach: unlicensed links for secondary or backup connections, and licensed links for primary backhauls that need guaranteed performance.

Point-to-point links can be deployed indoors (or on campus grounds) for short-range bridging, or outdoors for long-range connectivity. The needs and challenges differ between these scenarios. The table below contrasts **indoor/short-range** PtP applications with **outdoor/long-range** ones:

| Factor | **Indoor / Short-Range PtP** | **Outdoor / Long-Range PtP** |

|---------------------|-----------------------------------------------------------------|--------------------------------------------------------------------|

| **Typical Range** | Very short to moderate distances – from within one room up to a few hundred meters (e.g. across a campus or between two nearby buildings). Primarily line-of-sight but might tolerate slight obstructions at very short range. | Extended distances – from several hundred meters to many kilometres (links between buildings city-wide or across rural areas). Requires clear line-of-sight over the full distance (often with Fresnel zone clearance). |

| **Environment** | Controlled indoor settings or campus environments. No rain or wind indoors; easier to maintain equipment (climate controlled). Minimal weather impact (aside from maybe going through windows or walls which reduce signal). | Outdoor elements in play. Equipment must handle weather (rain, snow, wind, temperature extremes). **Weather conditions directly affect link** – e.g. heavy rain causing fade on high-frequency links. Outdoor links need weatherproof enclosures and rugged mounting to remain stable through storms. |

| **Equipment & Mounting** | Compact all-in-one bridge units or even standard Wi-Fi APs configured as bridges. Often low-profile antennas (panel or small dish) since distance is short. Mounting can be simple (on a wall, ceiling, or window inside a building). No special weatherproofing needed indoors. | Specialized outdoor radios with high-gain antennas (large dishes or flat panels) to reach target distance. Sturdy mounting on poles, masts, rooftops, or towers is required for alignment and to withstand wind. All gear must be **IP65+ weather-rated**. Often uses Power-over-Ethernet with shielded outdoor cabling, and proper grounding for lightning protection. |

| **Interference Profile** | Indoors, other Wi-Fi devices can be a source of interference (especially on 2.4/5 GHz). However, because range is small, the PtP link can use strong signal and less likely to pick up far-off interference. The closed environment limits external noise (no neighbouring WISPs inside your building). That said, reflective surfaces indoors can cause multipath interference, which modern MIMO technology can mitigate. | Outdoors, especially for long range, the link may be exposed to interference from other wireless systems in the area (other PtP links, radar, etc.). The **noise floor** can be higher. If using unlicensed bands, careful channel selection and spectrum scanning are needed to find a clear frequency. Additionally, long links can experience self-interference issues if multiple PtP links are on the same tower (need coordination). Licensed outdoor links avoid external interference by regulation. |

| **Bandwidth Needs** | Often used for LAN extension, so high bandwidth is beneficial (to match wired LAN speeds). Short links can easily achieve high throughput (even multi-gigabit with 60 GHz or WiGig bridges) since distance isn’t the limiting factor. Indoor use might also include **temporary high-speed links** (e.g. moving large data between two systems quickly in a lab via a short 10 Gbps wireless link). | Ranges from moderate to very high. Some outdoor links in rural areas might only need ~50 Mbps to connect a single remote site, whereas a backbone link might require 1+ Gbps. Long distance plus weather might cap the practical bandwidth (you may design a 100 Mbps link over 20 km because that’s what can reliably go that far with given antennas). Outdoor PtP often carries aggregate traffic (multiple users or sites), so it’s dimensioned for current and future capacity – which could be hundreds of Mbps to gigabit+. |

| **Regulatory** | Indoor bridges typically use unlicensed bands (standard Wi-Fi frequencies) and low power – regulatory concerns are minimal beyond using certified low-power devices. No licensing needed. (One exception: if an indoor link is going through an outside-facing window using high power, it might effectively act like outdoor and be subject to outdoor rules like DFS on 5 GHz). | Outdoor links may trigger additional regulations: e.g. **DFS (Dynamic Frequency Selection)** requirements on 5 GHz to avoid radar interference, which can occasionally pause a link when radar is detected. High-gain antennas must meet EIRP limits. If using licensed bands, regulatory process must be followed (prior licensing, link registration as with 70/80 GHz. |

| **Common Use Cases** | – Connecting two rooms or buildings on the same campus (wireless bridge as cable replacement within a site).<br>– Temporary links for events or debugging (set up a quick link in a conference hall).<br>– Industrial: linking equipment in a factory where running cable is hard (short-range link across a warehouse floor). | – Long-haul connectivity for ISPs and telecom (tower-to-tower links, rural broadband backhaul).<br>– Connecting branch offices in different locations, or municipal networks (e.g. linking city buildings, public safety networks).<br>– Connecting remote sensors or cameras over long distances (e.g. linking an oil rig to onshore control).<br>– Cross-border or inter-campus links where fiber is impractical. |

Both scenarios share the fundamental PtP principles, but the scale and external factors differ. **Indoor/short links** are often simpler and more forgiving – you can deploy quickly with little paperwork. **Outdoor/long links** require thorough planning (path surveys, spectrum analysis) and robust design to ensure a stable, legal operation. The benefit is that both make use of the same core idea – using the air as a cable – to solve connectivity challenges that otherwise require significant infrastructure.

A variety of networking vendors provide specialized point-to-point wireless hardware. Below is a list of commonly used brands and example models, along with typical application niches for each. These illustrate the range of options from affordable short-range bridges to carrier-grade microwave systems:

- **Ubiquiti Networks:** A well-known brand offering cost-effective PtP gear popular with enterprises, WISPs, and security integrators. Notable models include the **NanoBeam AC** and **PowerBeam** (5 GHz bridges for up to ~15+ km links), and the **AirFiber** series. *AirFiber 5X/5XHD* radios (5 GHz) and *AF-11FX* (licensed 11 GHz) are used by many WISPs for mid-range backhauls. Ubiquiti also offers 24 GHz and 60 GHz solutions: e.g. the **AirFiber 24** (24 GHz unlicensed, ~1.4 Gbps for several km) and **AirFiber 60 LR** (60 GHz “long range” up to 2 km). For easy enterprise links, their **UniFi Building-to-Building Bridge** (UBB) is a 60 GHz kit with 5 GHz failover, often used for short campus connections. *Use cases:* Small ISP backhauls, campus building links, CCTV connections, anywhere a good balance of performance and low cost is needed.

- **Cambium Networks:** Cambium (formerly Motorola Canopy) provides a wide portfolio of wireless bridge solutions from unlicensed to licensed. For example, the **ePMP Bridge-in-a-Box** is a plug-and-play 5 GHz kit for enterprise or camera links. On the higher end, Cambium’s **PTP 550** (5 GHz, 802.11ac Wave2) can aggregate two channels for ~1.4 Gbps throughput – useful for heavy enterprise links or WISP backhaul. In licensed bands, Cambium offers the **PTP 670** and **PTP 820** series: PTP 670 is a flexible sub-6 GHz radio (can do 4.9 GHz public safety band or 5.x GHz) with rugged build for industrial use; PTP 820/850 are **licensed microwave** solutions (6–38 GHz and 11/80 GHz respectively) delivering carrier-grade performance (Gbps speeds, high reliability for telecom). Cambium gear is known for good interference tolerance and features like GPS sync. *Use cases:* ISPs requiring reliable backbone links, government and enterprise networks (Cambium is often found in utility companies, city networks, etc.), and high-capacity industrial links.

- **Siklu:** A specialist in **millimetre-wave (mmWave)** links, Siklu focuses on 60, 70, 80 GHz equipment which provides fibre-like speeds. Their **EtherHaul** series is widely deployed for urban gigabit connectivity. For example, the *EtherHaul EH-600* is a 60 GHz radio for short links (up to ~1 km) at ~1 Gbps. The *EtherHaul EH-1200/1200FX* and newer *EH-8010FX* operate in the lightly-licensed 70/80 GHz E-band, with the EH-8010FX capable of 10 Gbps full-duplex. Siklu radios are often used by carriers or city broadband projects that need high capacity (like 5G small cell backhaul, or connecting surveillance camera hubs with multi-gig demand). *Use cases:* Fibre extension in metro areas, 5G/backhaul, campus links requiring multi-Gbps. (Siklu’s solutions are high-end, used where top performance is needed. As noted, their E-band links require simple FCC registration in the U.S.)

- **MikroTik:** MikroTik produces affordable networking gear, including PtP wireless devices favoured by budget-conscious users and hobbyists, as well as some WISPs. Their **RouterBOARD** hardware and RouterOS allow flexible configuration. Popular PtP models include the **MikroTik SXT** series (integrated 5 GHz units for short to mid-range links, often used for linking IP cameras or neighbouring buildings) and **MikroTik LHG** series (Light Head Grid, a dish antenna with built-in radio, good for longer 5 GHz links up to several km). MikroTik also innovated in 60 GHz with products like **Wireless Wire** – a pair of 60 GHz 802.11ad units pre-configured to provide an encrypted 1 Gbps link out of the box (ideal for <200m links, even through windows at short range). There’s also a **Wireless Wire Dish** variant with larger antennas to reach 1.5 km at 1 Gbps. While MikroTik gear may not always match the highest throughput of competitors, it’s valued for its versatility and low price. *Use cases:* Short links for small ISPs or CCTV (where budget is key), IT tinkerers connecting homes or remote cameras, and as backup links. Enterprises have also used MikroTik 60 GHz as a quick solution for building connectivity.

- **Mimosa (Airspan):** Mimosa is known for hybrid fibre-wireless solutions and is popular in the WISP community. Their **B series** radios are designed for point-to-point backhaul. The **Mimosa B5** (5 GHz) and B5c (connectorized version for external antenna) can deliver up to ~1 Gbps using 802.11ac technology and unique collocation features (allowing multiple B5 units on one tower). The **Mimosa B11** is a licensed 11 GHz radio (up to ~1.5 Gbps) for links requiring more reliability than 5 GHz can offer. They also have the **Mimosa B24**, a 24 GHz unlicensed bridge, which provides ~1.5 Gbps for short distances (1–3 km), useful for city links that need higher capacity than 5 GHz but without the licensing of 80 GHz. Mimosa focuses on easy deployment and price/performance, making them a competitor to Ubiquiti and Cambium in the ISP space. *Use cases:* Rural ISP backhauls (where 5 GHz is congested, B11 licensed links provide relief), short metro links (B24 as a quick gigabit pipe), and enterprise connections needing good throughput at moderate cost.

- **RADWIN:** RADWIN offers carrier-grade wireless solutions and is often seen in **transportation, government, and ISP networks** for robust connectivity. The **RADWIN 2000** series are point-to-point radios in sub-6 GHz bands that are known for reliability in harsh conditions (some models support both licensed and unlicensed bands). RADWIN’s PtP solutions often incorporate proprietary protocols for interference mitigation and long range. For instance, RADWIN links have been used for CCTV and traffic monitoring networks where stability is critical. They also have JET series and others, but those are more PtMP. A notable aspect is RADWIN gear’s ability to maintain link quality in noisy environments – this makes them popular for city deployments where lots of wireless signals exist. *Use cases:* Critical camera links (e.g. connecting railway surveillance to control centers), rural ISP links requiring high reliability, oil & gas field communications. RADWIN is a bit more premium, similar to Cambium, focusing on consistency over cheap throughput.

When choosing hardware, one should consider the required frequency (does it need to be licensed?), range, and throughput, then select a brand/model that fits those criteria. Community forums (WISPs, networking professionals) are filled with debates on these brands – each has strengths: e.g. Ubiquiti for affordability, Cambium/RADWIN for reliability, Siklu for ultra high capacity, etc. Often, **real-world experience and support availability** influence the choice as much as spec sheets.

Deploying a point-to-point wireless link requires attention to several practical and technical factors beyond just buying the radios. Here are additional considerations to ensure a successful PtP deployment:

- **Line of Sight & Fresnel Zone:** As emphasized, clear line-of-sight is crucial for most PtP links. Before deployment, do a survey (even a simple visual check or using mapping tools) to confirm no buildings, trees, or hills block the path. Remember the **Fresnel zone** – the football-shaped area around the line-of-sight path that should be mostly clear to avoid signal diffraction loss. Even if you can “see” the other side, an object encroaching on the Fresnel zone (like tree tops or a flagpole) can weaken the signal. Aim for at least 60% of the first Fresnel zone radius clear of obstructions. If minor obstructions exist, consider using a lower frequency (which has a larger Fresnel zone but diffracts better) or raising antenna height. **Alignment** is also key: take time to precisely aim the antennas during installation, using alignment tools or the radio’s signal strength readout. A narrowly focused link (like 60 or 80 GHz) might require two people coordinating or special alignment scopes due to very tight beamwidth.

- **Mounting & Structures:** Proper mounting hardware and stable structures are a must. Outdoors, use mounting brackets rated for the antenna size – large dishes need heavy-duty mounts to prevent movement in wind. Even a slight movement can misalign a long-range link. Poles or masts should be rigid; if mounting on a building, choose a wall or roof mount that minimizes sway (avoid flimsy poles that oscillate). If on a tower, ensure the antenna is well clamped. Vibration or sway will show up as fluctuation in link performance. Additionally, consider the ease of access for installation and maintenance – you might need to align at height, so safety and accessibility matter. Indoor mounts are simpler (often just attaching to a wall or ceiling), but still ensure the alignment doesn’t get bumped by people or objects.

- **Power and Connectivity:** Most PtP radios use **Power over Ethernet (PoE)** for simplicity – delivering power and data through one cable. Plan how you will power each end: if there’s no AC outlet near the rooftop installation, PoE from an indoor injector or switch port is ideal. Ensure the PoE injector or switch meets the device’s voltage requirements (24V passive PoE for some, 802.3af/at for others). Use **shielded outdoor-rated Cat5e/Cat6** cables for outdoor runs, and ground the cable shield to protect against lightning. If the cable run is long, remember Ethernet has a 100m limit – you might need a midpoint switch or PoE extender for very long runs. Also consider backing up the power – if this link is mission-critical, put the powering equipment on a UPS so that a power outage doesn’t drop the link.

- **Weatherproofing:** Outdoor equipment should be rated for the environment (temperature, moisture). Ensure all cable connections are weatherproofed – use proper gland connectors or weatherproof tape on RJ45 connections to prevent water ingress. Antenna feedhorns or radios should have protective covers as designed. If you’re in a lightning-prone area, implement **lightning protection**: this means grounding the antenna masts and using Ethernet surge protectors near the entry point of the cable to the building. Over many years, sun exposure can degrade plastic components – industrial-grade gear will survive UV, but keep an eye on any cable ties or plastic mounts that might brittle over time.

- **Spectrum Planning:** Do a spectrum scan (many radios have a built-in scanner) before finalizing the frequency channel, especially in unlicensed bands. Identify what frequencies have the least interference at your site. It’s good practice to **avoid using default channels** if they are crowded. In 5 GHz, be mindful of DFS requirements – if your link must use a DFS channel (to get a clean spectrum), the radios will need to be able to handle radar detection events (which can cause the link to go down for a short period while the channel is vacated). In crowded areas, sometimes the solution is to use a narrower channel or lower band to get a reliable link (trading some throughput for stability). If using multiple PtP links from one location, plan the channel usage and maybe use different polarization or enough frequency separation to minimize interference between your own links.

- **Legal/Regulatory Compliance:** Always ensure you operate within local regulations. For unlicensed bands, this means respecting power/EIRP limits, using approved equipment, and following any dynamic frequency selection rules. For example, in some countries outdoor use of 5.8 GHz may have an EIRP cap (e.g. 36 dBm); if you use a high-gain antenna, you must reduce radio transmit power to stay under the limit. For licensed bands, **coordinate and obtain licenses** well ahead of deployment – you may need details like exact coordinates, antenna gain, height, and desired frequency. Regulators often provide guidelines or online tools for link registration (e.g., the FCC’s E-band registration system for 70/80 GHz). Non-compliance can lead to fines or forced shutdown, so it’s not optional. Also, if you’re renting a roof or tower space, check if there are any restrictions by the property owner or if you need an agreement to install your link.

- **Line Capacity and Future Growth:** When designing a PtP link, consider not just current needs but future needs. If an enterprise currently needs 200 Mbps between sites but plans to implement high-res video conferencing or large data backups between locations, it might soon need 500+ Mbps. It could be wise to choose a solution that can scale (either via software license upgrades, channel bonding, or simply initial over-provisioning of throughput). Replacing a link later can be costly, so balancing current budget vs. future-proofing is important. Similarly, consider if you might later need a Point-to-MultiPoint (PtMP) setup – some radios can act in either PtP or PtMP mode (e.g., Cambium ePMP or Ubiquiti airFiber can be repurposed in some cases). If there’s a chance a single PtP link might evolve into a hub serving multiple sites, you might pick a platform that supports that expansion.

- **Security:** Treat a wireless bridge like any network connection – secure it. Many professional PtP devices support encryption (AES-128/256) over the link – use it if sensitive data is traversing. Also, secure management interfaces (change default passwords, use HTTPS/SSH for management). While intercepting a well-aligned narrow PtP beam is difficult without physical proximity, it’s still best practice to encrypt wireless links (and some regulations or industries require it).

- **Redundancy and Failover:** If the link is critical (e.g., an ISP backhaul or important enterprise link), plan for redundancy. This could mean **setting up a second PtP link** in parallel (perhaps on a different frequency or path) to failover if the primary link fails. Some setups use dual links and configure them in a failover bond or even active-active aggregate if the equipment supports it. Alternatively, have a contingency like an LTE/5G backup or a lower-capacity licensed link standby in case the unlicensed primary link experiences interference. Redundancy is extra cost but can save a network outage down the line.

By accounting for these considerations – **line-of-sight, mounting stability, power, weather, spectrum, and regulations** – you greatly increase the chances that your point-to-point wireless link will deliver the expected performance over the long term. In real-world deployments, attention to such details often makes the difference between a rock-solid link and one that intermittently fails. With careful planning and the right hardware, PtP wireless is a proven solution to extend networks reliably and cost-effectively where wires can’t reach.