MPLS over microwave

[andyaoyao]

Hi,

We want to build a MPLS core network using microwave equipment.

In some situations there could be multiple microwave links between two routers, as below.

R1  ----m1-----m2-----m3---- R2

R1 and R2 are routers running MPLS.

m1~m3 are microwave bridges.

Since R1 and R2 talk in MPLS, but m1 ~ m3 don't, can we still access m1 ~ m3 remotely (via IP, TCP) ?

(assume R1, R2, m1 ~ m3 have interfaces in the same subnet.)

Another question.

Will the delay in microwave links causes troubles for AToM and VPLS?

Thanks,

-Andrew

[blau grana]

Hi,

The answer is that it depends...

You need to run some kind of IGP between R1 and R2 so these routers have to be L2 adjacent. You said that mx are bridges, do they support jumbo frames? With services like MPLS VPN or AToM,... size of L2 frame is bigger [mtu/mpls mtu] so make sure that this will not be issue. L2 frame could have 1522B or even more.

Regarding mx management, I probably would not design network where R1,R2 interfaces and mx bridges are on same subnet, but it should probably work.

Maybe better solution would be if you create subinterfaces on routers, native vlan with one subnet will be used for mpls network and other vlan [lets say vlan50] wil be used with another subnet for radio management.

Best Regards

Please rate all helpful posts and close solved questions

[andyaoyao]

Thank you for the advices, blau!

Suppose we have 8 core MPLS routers with similar setups on the network, is there a way to separate core network and radio management network? (We will run OSPF with probably only Area 0)

Do we need to run a second OSPF process for the radio mgmt?

Will the sub-interface know the radio mgmt LAN is not MPLS and deliver the packets wihtout MPLS label?

When we issue "mpls ip" command, should we do it on interface level or sub-interface level?

Yes. The radio supports jumbo frame.

Thanks!

-Andrew

[blau grana · Accepted solution]

Hi Anrdew,

Sorry for a late response.

As I said, it is better if radio's mgmt would have separate vlan, but I think you don't have to run separate routing process for them.

With "mpls ip" command you will enable labeling packets on particular interface. So if you create two subinterfaces (first for mpls connection to other router and second for radio mgmt) mpls ip command will be applied to only first subinterface.

If you will advertise radio mgmt via IGP, make sure that mgmt links have increase cost (ip ospf cost 1000) so IGP will not choose this link as the best.

Second solution could be using IGP only for advertising loopback and mpls links between routers. And BGP will be used for advertising radio mgmt links -> this solution is dependant on your topology, because you need to run BGP on all routers.

If you have some sketch of your topology it would be very helpful.

Best Regards

Please rate all helpful posts and close solved questions

[andyaoyao]

Hi blau,

The topology is like below.

F--E--D---A
      |   |
      |   |
H--G--C---B---J

I thnk I will take the first approach and put radio mgmt to a 2nd sub-interface.

Thank you!

-Andrew

[Istvan kelemen]

Hi,

You shall issue mpls ip only under the subinterface.

If the MW supports vlans you can directly connect the router to the MW. If now you shall use a switch.

I work for Orange CH, they use different vlans for mgmnt and for data plane.

The network has one vlan for MW mgmnt, one for BTS mgmnt and one for data plane.

What kind of MW do you use?

Let say we have Ericsson TN's

          Vlan10 - data plane

R1------------------TN6---------TN6----------TN6--------------R2

          Vlan20 - mgmnt

in this case you need to configure the MW as a switch.

[andyaoyao]

Hi kelemen,

Thank you for the insight!

We haven't decided the MW vendor yet.

I will pay attention to the VLan implementations.

Thanks a lot!

-Andrew