PoE based IP cameras need a steady bandwidth of about 1 mbps per megapixel resolution in case of H.265+ and up to 5 times this in case older H.264/H.264+ cameras are used. These cameras usually do motion triggered recording at the NVR only (as cameras do not have PIR sensors) by comparing frames. H.264+ is on its way out in these cameras and will be universally replaced by H.265 in a few years time and H.265 is remarkably efficient as resolution increases and bandwidth/storage does not grow linearly always as resolution increases.
Whatever be the outcome of this predication, the fact remains that no IP camera need more than 100 mbps or fast ethernet bandwidth even for higher resolutions, and most not even 10 mbps. This is not expected to change in the near foreseeable future. Therefore, to support such bit rates only a cat 5/5e twisted pair ethernet cable with 2-pairs are sufficient. Whereas a cat5e cable commonly available in market will have 4-pairs and support 100 mbps for 100m length, and a cat6 would do 1000 mbps for 100m length. Therefore its absolutely not required to use cat 6 cables for IP cameras and cat 5/5e is just good enough. You should skip cat 6/6a and save the extra premium for something else.
Generally conductors 1-2-3-6 (pairs) are used in an ethernet cable for IP cameras and power & data is sent on the same pairs by PoE switches (endspan devices - Mode A PoE). However some older NVRs and PoE injectors (mainly midspan devices - Mode B PoE, some or not all which are not fully 802.3af/at standard compliant) prefer to use the spare pairs (4-5-7-8) and this may cause problems of inter-working with some IP cameras and injectors/NVRs. It is also rare to find cables with 2 pairs and some cameras would not support 2-pair cables for PoE. Further in-depth analysis on this subject can be had from this URL.
Therefore you may stick to regular 4-pair cat 5e of good quality . It will give you the added flexibility of splitting the Ethernet cable to support two cameras of one cable in future( as shown below), plus be generally compatible with most camera brands and models.
Generally conductors 1-2-3-6 (pairs) are used in an ethernet cable for IP cameras and power & data is sent on the same pairs by PoE switches (endspan devices - Mode A PoE). However some older NVRs and PoE injectors (mainly midspan devices - Mode B PoE, some or not all which are not fully 802.3af/at standard compliant) prefer to use the spare pairs (4-5-7-8) and this may cause problems of inter-working with some IP cameras and injectors/NVRs. It is also rare to find cables with 2 pairs and some cameras would not support 2-pair cables for PoE. Further in-depth analysis on this subject can be had from this URL.
Therefore you may stick to regular 4-pair cat 5e of good quality . It will give you the added flexibility of splitting the Ethernet cable to support two cameras of one cable in future( as shown below), plus be generally compatible with most camera brands and models.
However be careful and not use using cat5e cables in switch-switch links. These links may require more than 100 mbps throughput for upto 100m in case copper and Optical Fiber for longer runs and therefore cat 6/6a or OFC is a better fit and can support speed such as 1 gbps., 2.5 gbps, 5 Gbps and 10 Gbps. cat 5e can support 1000 mbps for upto 33m only or very short lengths.
DISCLAIMER: Exception to the above assertion is deployment of cameras in very high EMF requirements (we haven't found one in a residential complex setup), where the headroom of Cat 6 and cat 6A is higher (23 AWG/250Mhz and 22AWG/500 Mhz respectively compared to 24AWG/100 Mhz of Cat 5e) makes it a better choice at the expense of more cable weight, cable stiffness and diameter, installation difficulty, etc.
- Suman Kumar Luthra @ APRC-P3 Telecom Sub-Committee
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