Site-to-site VPN, WAN Protocols, VoIP and load balancing

[dylan.murray]

PLEASE HELP!

I am totally stuck and have been working on packet tracer for days trying to find a solution to this. The main protocols I am thinking about using are EIGRP and BGP for this.

I am working on a project with 5 sites. one site is the HQ which I want to set up a hub and spoke VPN connection.

The client has purchased a full addressing space with 16 public addresses. The main site is configured with the 2 highest and the ISP takes the 2 lowest on that side. The configuration doesn't work for me because the Router will only accept one of the IP addresses as they are on the same network so there is an overlap.

I'm confused because our problem description specifically says that the edge router has been configured with these addresses

There is also a second backup HQ that we plan to implement load balancing using a further 2 addresses with the edge router if possible. There will be a Hub and spoke VPN set up that will carry data from site-to-site passing through the HQ site. I think I will be able to do this no problem but it is the IP addressing that is confusing me or stopping me from carrying on.

Also. We want to ensure that if a link between the branches and the main site fails, then a new link would pick up again after 10 seconds. Is this something that BGP can provide?

Lastly. If I want to implement a VoIP traffic into the network over WAN does everything get set up on the router or will I need a specific VoIP server in the HQ providing IP's etc to every phone.

What am I doing wrong or overlooking here because I can't seem to work up a solution for this that doesn't involve have 2 routers working on the edge which isn't practical at all. 

Please help and give any advice/directions on what I can do here.

Thanks in advance

Dylan

[Manish Gogna]

Hi Dylan,

I can comment on the VoIP part.  You ca have primarily three types of Cisco Unified Communications Manager ( CUCM ) based Deployments:

1> Single Site ( where all servers, routers, switches, endpoints are located  at one site )

2> Multisite with Centralized Call processing ( where the CUCM servers are located at HQ only and remote sites have endpoints registering to CUCM servers at HQ site across the WAN )

3> Multisite with Distributed Call processing ( where CUCM servers are distributed across different sites to provide call processing and registration functions )

In your case it appears you have option 2. In that case the router on remote site should be configured with SRST ( Survivable Remote Site Telephony ) feature so that in case the WAN link between the remote site and HQ site is down the phones can register with the local SRST enabled router instead of CUCM to carry out the call related and other functions. DHCP can also be configured locally in the remote site on same router  to provide IP addresses to the IP phones in those locations. CUCM also has the options to provide DHCP services but is generally not used for remote sites. SRST feature is enabled via a license and you can refer the following link for the various platforms supporting SRST as well as their capacities

http://www.cisco.com/c/en/us/support/unified-communications/unified-survivable-remote-site-telephony/products-device-support-tables-list.html

You can refer the CUCM design guide as well for details about CUCM based design recommendations.

HTH

Manish