Connecting 2 MPLS networks together

Need some advice on connecting 2 MPLS networks together from two different ISPs. The compnay I am working with is using AT&T MPLS and they aquired a smaller company using SBC MPLS. We want to connect the two networks together for the shorterm and eventually the goal would be to add te new sites to the AT&T MPLS.

You have two options here,
1) you can talk to you SP regarding the situation and they should be able to put across a inter-AS solution for you, and this should be possible looking at the close ties between ATnT and SBC.
2) If you plan to go ahead with this on your own, since its only a transitionary situation, you can think of interconnecting both the networks core at the closest possible location terming them as border gateway routers. And then keep migrating the smaller companies sites to the your existing SP's network.
But do note that if there are overlapping IP addresses between both the networks then you may have to consider a NAT gateway in addition to the border gw routers. If you plan to use the Inter-as option, the SP would have a NAT gw solution for the same.
Overall you need a crystal clear plan before you go ahead with any of the options.
HTH-Cheers,
Swaroop

Similar Messages

  • Connectivity problems on ATM MPLS network

    We have implemented a country wide MPLS network based on 8500 platforms. We have encountered some strange connectivity problems between some PE's. Without apparent reason connectivity is lost between some PEs and restored after some time. The global routing table is perfectly stable among all the routers on the path between respective PE's. Also the LVC's & TAGs are stable and practically we were unable to find any change between the working and not working state. As a curious thing, during the outage (minutes) clearing routes into a PE VRF was restoring connectivity on the respective VRF and all other VRFs on the respective PE also!
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    Have you made any provisioning (upgrading connectivity) bet the PEs and Ps....I suffer such a similar problem with our network PEs and I notice that this happen after provisioning links between our PEs (RPMs in MGX 8850) and the ATM LSR (BPX 8600).
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  • Access local mpls network surf internet with pda(gprs/edge/3g connection)

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    The
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    Please click “Accept as Solution " if you feel my post solved your issue, it will help others find the solution.
    Click the “Kudos, Thumbs Up" on the right to say “Thanks" for helping!
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  • Running Large Backups over an MPLS Network

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    "Do you think MPLS is a good technology to run large back ups across?"
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  • MPLS Network Backup

    We have a MPLS network between Head office & varios branch office located across the globe. Can you suggest me the best possible backup(automatic) for this MPLS? as we are facing lot of breaks/cuts in the MPLS Network.

    This is to give a fair idea.
    Pls modify the conifg to suit your setup.
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    network 192.168.3.0 0.0.0.255 area 1
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    HTH-Cheers,
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  • Influencing BGP attributes within MPLS network

    pls take a look at my question and diagram is attached in the file. pls help me to fix this problem.
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    route-target export 1:20
    route-target import 1:40
    export map EXPORT-ROUTE
    import map IMPORT-ROUTE
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    ip vrf forwarding CUSTOMER
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    neighbor 1.1.1.1 soft-reconfiguration inbound
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    no synchronization
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    ip extcommunity-list 2 permit rt 1:40
    route-map EXPORT-ROUTE permit 10
    description LONDON-GW
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    set extcommunity rt 1:20 additive
    route-map IMPORT-ROUTE permit 10
    description EU & US-BRANCH
    match extcommunity 2
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    ip vrf CUSTOMER
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    route-target import 1:40
    export map EXPORT-ROUTE
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    import map IMPORT-ROUTE
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    Hi Manoj
    "send-community both" will export both Standard and Extended Communities
    The Standard Community Values which we are setting up New on PE3 and PE4 and Matching on PE1 and PE2 can be anything in ASN:nn Format..I Just randomly chose them as 65400:1111 on PE3/PE1 and 65400:2222 on PE4/PE2.
    The extcommunity values to be used on PE3/PE4 will be the export RT values used in the VRF Customer Config as posted in your first post..
    #PE3
    ip vrf CUSTOMER
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    route-target export 1:20
    route-target import 1:40
    export map EXPORT-ROUTE
    import map IMPORT-ROUTE
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    ip vrf CUSTOMER
    rd 1:10
    route-target export 1:30
    route-target import 1:40
    export map EXPORT-ROUTE
    import map IMPORT-ROUTE
    I think I mixed up little with PE3 as PE1 and PE4 as PE2 instead ..Revised corrected config would be
    On PE3-- Under VPNv4 We enable sending out the normal community values out to the RR.Then we match the extcommunity rt for the VRF Customer and set the community value to 65400:1111 which will be matched at PE1
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    On PE4-- Under VPNv4 We enable sending out the normal community values out to the RR.Then we match the extcommunity rt for the VRF Customer and set the community value to 65400:2222 which will be matched at PE2
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    route-map community permit 10
    match community CUSTOMER
    set local-preference 110
    route-map community permit 20
    ip community-list standard CUSTOMER permit 65400:2222
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    Hope this helps to answer your question..Please let me know for any clarifications..
    Regards
    Varma

  • Debugging and monitoring MPLS networks

    Hi ,
    I've had the following problem with a customer of ours and I'd like to know if there's any tools I can use in the future to better diagnose the problem if it may arise again.
    The customer is a bank with hundreds of brnach sites. All of them are connected to the corporate via a MPLS network managed by a local TELCO company .
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    Next I tried looking at the network connections with the few tools I have ( basically ping , traceroute and protocol analyzer ) but all seemed ok .
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    havent not told us what the actual problem was it is kinda difficult to suggest tools. However IF this was an MTU issue then you should have used ping with the DF bit set to see how big a packet you could get over the mpls network. Let us know what the issue was and hopefully we can be a bit more detailed in our responses.
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  • Routing Protocol recommendation for MPLS Network

    I am in the process of building a 14 site MPLS network for voice and data traffic. The vendor installing the network has configured RIPv2 as the routing protocol. I am considering switching this over to EIGRP. Can anyone explain to me why this would be better or should I just stay with RIP.
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  • Routing to MPLS network

    Hi,
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    Said
    Is the LAN switch layer 2 only or layer 3 capable. If you do not have access to the MPLS router you have 2 options
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  • Venturing into MPLS Network

    Hi all, it is just my curiousity that ended up with a small discussion like this. Here's about it...
    My company has a main client which have tonnes of remote sites connecting to both their HQ and Disaster Recovery Centre. Some of the remote sites still running on frame-relay, while other is purely leased-line. There's a few question I wish I can clear up as follows:
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    ii. Even if comparing to leased-line services, what kind of advantages I can expect if our cliet migrate over to leased-line?
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    Hello,
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    This would be the case when you migrate from FR to MPLS VPN and do not shut down FR the very moment you activate the MPLS links.
    What can happen in this scenario is: CE1 is announcing Network N1 through RIP to CE2 directly over the FR PVC and also to PE1. PE1 will redistribute N1 into MBGP, send the prefix to PE2, which will redistribute N1 into RIP and send the update to CE2.
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    The problem might occur once CE1 looses network N1. It will send an update directly to CE2 and to PE1 and a race condition exists. CE2 will still have one valid path to N1 learned from PE2 and announce this one to CE1, which will announce it to PE1 and then PE2, CE2, CE1 again and so on.
    This is an intermittend or even persistent routing loop, depending on what you have done with hop count during redistribution.
    By designing your overall routing solution carefully you can avoid this scenario.
    Hope this helps! Please rate all posts.
    Regards, Martin

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