Redundant proxy with SPA 502

[m.kabbashi1]

Hello,

I read the article on

https://supportforums.cisco.com/document/59936/configuring-sip-proxy-redundancy

1- Is it ideal if I used SPA 502 or its better to avoid this method and use phone with multiplelines like SPA 504?

2- What the limitation should I expect if I used this method?

3- What the delay time expected of checking availability of first proxy then going to the second proxy?

Thanks in advance

[Dan Lukes]

1, It depend on your expectation & usage patterns. Also, you didn't disclosed how you wish the SPA504G will be used as a replacement, so we can't compare.

2. So vague question to answer, sorry.

3. Its "Register expires" configuration value.

[m.kabbashi1]

Hi

1- in other words, what really the benefit of phone with more than one line?, as I am confused what I will get from using multi-line ip phone like SPA 504.

For redundancy I found that on line phone like SPA 502 can do the job with configuration of primary proxy and secondary. That eliminate the need to have more than one line as I was trying to get multiple line for backup/redundancy purpose.

2-  I mean , if I configured redundancy inside SPA 502 to have backup proxy , what the limitation of this method?

3- is it in terms of seconds? what the optimal?

Thanks :)

[Dan Lukes · Accepted solution]

1a) I need not to have eight independent phone devices on my desk. I have eight distinguished phone numbers located on six SIP switches configured on one SPA508G instead.

1b) Even our casual users with just one phone numbers have SPA504G. We are unsatisfied with internal implementation of DND and forwarding features inside of SPA5xx thus we use our own. Spare line LED are used to signal {DND|CFU} {on|off} to user as vendor defined PSK keys can't be driven reliably from switch side.

In short - multi-line IP like SPA504G will provide you multiple lines. It can be considered big benefit if you need them for a purpose. It's no benefit if you have no usage for them.

2. I still don't understand the question. You know the backup method used thus you know the overall behavior. What other "limits" are you asking for ?

3. Consider reading Administrators guide, please. Yes, it's in second. No, there is no generic optimal value. It depend on your needs and expectations.

[m.kabbashi1]

Thanks :)

1b) what is Spare line LED,CFU,PSK?

2- If I configured redundancy inside SPA502, is there any limitation that I should take it in my account? I dont know if there is or not , it's assumption.

so if yes ,what this limitation, if no that means everything is fine with configuration redundancy in this phone.

Thank you

[Dan Lukes]

Spare line LED is the line led not assigned to particular extension.

CFU stands for Call Forwarding Unconditional

PSK is the Programmable Shared Key

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Please understand - we known nothing about your network, overall configuration of your switches and your expectation. No one can respond what behavior of particular feature affect something in the way you will feel uncomfortable.

You know the behavior of redundancy and you know your network. You may evaluate overall interactions only.

[m.kabbashi1]

ok thanks