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New Member

voip over mpls

I am looking to reduce the monthly cost of dedicated private T1 to remote sites. At each site we have 5 staff users and up to 75 others that we provide internet access to at the building. At each site we have T1 for internet and 1 private T1 for data and voip. Would it make sense to cut the private T1 and run everything over the internet T1 via BGP/MPLS vpn?

Hall of Fame Super Gold

Re: voip over mpls

Yes, but you may encounter bandwidth problems. You should investigate about a fast connections at branches and run everything over the internet.

New Member

Re: voip over mpls

Thanks for the quick reply. The only internet access the service provider can give it T1 handoffs. Can internet t1 be bundled via multilink PPP?

To make things more complex. I guess what i need to know is once a MPLS network session is established over a internet t1. Does that interfere with other traffic running over the internet t1?

Would users be able to establish a vpn connection from their home to their network and servers at the remote site?

Site 1, Group1, WAN\Network 1, Subnet A, (5 users) connects to internet and mpls to corporate site for data over internet T1.

Site 1, Group2, Wan\Network1, Subnet B, (25 user) access to internet and be able to vpn to Subnet B from outside site1. they have asa5510 between the network we provide and their internal network.

Hall of Fame Super Gold

Re: voip over mpls

Yes you ISP should be able to bundle T1s, just ask,

You do not do MPLS over the internet, you do VPN.

All you're asking is possible, I recommend you configure DMVPN with the help of a reputable cisco partner or consultant.

Super Bronze

Re: voip over mpls

The problem with sending traffic across the Internet, there's usually no guarantees for service. This can be often mitigated to a great extent, if you can manage/control QoS on your link to/from the ISP because these links are usually the primary bottlenecks.

If the ISP won't allow QoS control on their side (and they often won't), you can indirectly manage their side if you only send corporate traffic across the link and carefully managage QoS at your other sites (much like you might do logically across a frame-relay or ATM WAN cloud).

To not share an Internet link for both corporate and raw Internet traffic usually means you need one Internet link dedicated for both. When you provide two Internet circuits, also keep in mind popular Internet circuits (e.g. aDSL, cable), might be fine for "raw" Internet access.

To provide best service guarantee w/o using two Internet links at all sites, remotes sites can access Internet across the "corporate" Internet provided by another site.

Generally, corporate traffic, with correct bandwidth management, I've found, tends to perform very, very well across the Internet. Real-time traffic, e.g. VoIP, can be "iffy".