Specifications

Network Configuration Specifics
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Figure 51: Using Wire Color Order to Identify Connection Cables
The cables shown are those expected in new installations, namely, a T568A connection to a
T568A for a straight cable, and a T568B connection to a T568A for a crossover cable. It is also
possible to get straight cables that have a T568B connection to a T568B, but these are more
likely in older installations.
International standards recommend that new installations conform to the T568A wiring format.
However, a number of current installations may have wiring to T568B. As long as a common
format is used throughout the installation, and there are no unexpected swaps, then electrically,
the color is less important (for example, all wall jacks to T568A or T568B, but not a mix).
IP Phone LAN Speed Restrictions
The IP phones are configured to auto-negotiate the LAN speed settings. Ensure that the Layer 2
switch setting is also configured to auto-negotiate to reduce the possibility of a duplex mismatch
and potential loss of data and voice.
Although IP phones auto-negotiate the network connection speed to 100 Mbps full duplex, note
the following limitations:
• Both ports on the phone are limited to the lowest negotiated setting.
• The 5001, 5005, 5201, 5205, and 5207 phones are configured for auto-negotiation, but are
limited to 10Base-T (10 Mbps) full and half duplex.