1.Does UC 500 support other vendor (HP) switches for IP phones? - I found in some threads that it works but not tested nor TAC supported. 2.Does UC 500 support other vendor (Siemens)wireless access point for wireless Phones and PCs? Our client already has HP switches and Siemens wireless access point AP2640 in place and would like to integrate UC 500.
The general principle that applies here is what you have already seen elsewhere. Using a UC500 in conjunction with non-Cisco network infrastructure is not something we test or support, but given all the protocol and technologies used are standards-based, there is no technical reason why this will not work.
The downside of a mixed infrastructure is that you become responsible for figuring out how everything needs to be configured to interoperate. Similarly, if you have a problem with a phone plugged into a third party switch, the first thing the support engineers will likely ask you is to plug the phone directly into a switchport on the UC500. If the phone works there, then they won't be able to help you any further. With Cisco infrastructure of course, you won't have that problem, because the same support team is responsible for helping you with all the equipment.
We use CDP which is a Cisco proprietary protocol to relay VLAN information from the switch to the phone. Most third party vendors won't run CDP, so you have to hard-code the port as an access port on the switch, and share the voice and PC VLANs.
Other than that, if you are comfortable configuring, troubleshooting, and supporting the switch, it should work fine in a UC environment. The access point should be fine, though you may want to make sure they have specifications/configurations for doing voice over the AP, as there are QoS considerations to take when doing voice over wireless.
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