Two sites linked via leased line, and single UC560 at head office

[graeme]

Hi,

I have inherited a site to be setup.

They have a HQ and sattelite office linked by a 2Mb Leased line with 1 x Cisco 1800 router at each end.

HQ runs 192.168.1.x subnet and Site 2 runs 192.168.2.X subnet.

They have purchased a UC560, with 48port ESW for HQ, and a 24Port ESW for Site 2.

They wish to run all phones from both sites on the of the HQ UC560.

I am unsure as to the best way to achieve this, is it better to extend the voice VLAN subnet to cover both sites, and setup routing accordingly, or is it possible to setup a seperate Voice VLAN for the second site on a 2nd subnet.

Or is this completely wrong and their is a better solution?

any help and advice owuld be appreciated.

Thanks

Graeme

[rcastill]

One possible solution to add to the mix is to add a UC540 at Site 2.   This will allow interextension dialing at Site 2 even if this leased line goes down for some reason.  You could also add some POTS lines at the Site 2 to allow for failover. 

Using CCA you can configure a multisite config very easily.  It generates an XML file that you then copy to the second UC at Site 2.  It will allow split-tunneling so that you can route all your internet requests out of a local gateway; by default all of these will route via the main site gateway.  In a county where connection to an ISP is expensive you could realize a cost saving by using the default.  If latency is a concern you can add split-tunneling later to address this.

Another great feature of the UC560/540 is that you can use floating extensions  to allow for 3-5 digit extension across the enterprise.  Assign the primary block of extensions to the main office (i.e. 200-250) and then assign a second block of extensions to Site 2 (i.e.250-280).  You will need to only dial the 3 digit extension at either location.  Use a floating extension to add the additional digits to your dialstring (i.e. 8+2+250)  8 denotes that this is a multisite and 2 denotes the site number to call.

All the best,

Robcast

[graeme]

Thanks Robert,

I had thought of that but the sales on the deal (which I iherited the setup of) has informed the client that they wont need telecoms at the 2nd site as they are leased line linked, and they have cancelled all services.

I have been asked to make it work I think it should be doable.

With regards to the second system setup, that is what is being done for a 3rd site which is linked via VPN, they ahve their own system and own incoming calls, for resiliancy, but the 2nd site wont.

Thanks for the tip on the floating extensions I will look to do that for the 3rd site.

Cheers

Graeme

[bjames]

Graeme,

Yes you can easily run both locations off the UC, the big and first question is what is the jitter and latency on the 2M link and will it be used for data as well.

If latency and jitter are fine, but you do want to use the link for data as well, you will need well defined end to end QoS will enough bandwidth reserved for the VoIP calls.

There are a few ways to do this, but I would use the LAN (not WAN interface) for the traffic.

Perhaps Cisco can make design recommendations as well.

Bob James

[mcasimirc63]

How many users are at each remote site?  You could easily have a UC560 + SR520 for the remote locations for a scenario where all the users appear to be on the same network.  Bandwidth constraints will be an issue if you have more than a couple users at each remote site.