mpls-linux-general

[mpls-linux-general] How ldp assigns labes

[Dragoescu A. <dra...@gm...>]

Hy,

 

I have a question ? How ldp assigns labels.Have this setup:

 

            B

A                      D

            C

 

A connected with B and C and D also 

Ok,after ospf will distribute routes , how ldo assigns labels.

On LSR A Ospf will distribute 2 routes with destination D.

LDP will create 2 LSP with destination D ?

 

As implementation how LDP will assign labes? It looks on ospf routing table
and for any destination will assign a new label?

 

10x,

AlexD

Re: [mpls-linux-general] How ldp assigns labes

[Marco S. <mar...@s2...>]

You mean a setup like this?

=A0=A0=A0=A0=A0 =A0 ---B---
      /         \
    A<=A0=A0=A0=A0=A0 =A0=A0=A0=A0=A0>D
      \         /
 =A0=A0=A0=A0=A0=A0 ---C---

This scenario doesn't work since you change the link cost (in OSPF) on one
link. The LDP-implementation doesn't support equal cost multipaths (ECMPs).

Routes are redistributed by the zebra routing manager, you may look at the
resources of quagga.net to see how the protocol deamons interact with
each other.

>    =20
>  =20
>  =20
> Hy,
>  =20
> =A0
>  =20
> I have a question ? How ldp assigns labels.Have this setup:
>  =20
> =A0
>  =20
> =A0=A0=A0=A0=A0=A0=A0B    A=A0=A0=A0=A0D
>
> =A0=A0=A0=A0=A0=A0=A0
>  =20
> =A0
>  =20
> A connected with B and C and D also=20
>  =20
> Ok,after ospf will distribute routes , how ldo assigns labels.
>  =20
> On LSR A Ospf will distribute 2 routes with destination D.
>  =20
> LDP will create 2 LSP with destination D ?
>  =20
> =A0
>  =20
> As implementation how LDP will assign labes? It looks on ospf
> routing table and for any destination will assign a new label?
>  =20
> =A0
>  =20
> 10x,
>  =20
> AlexD
>  =20
>  =20
>    =20

--=20
Marco Schmidt
mailto:mar...@s2...

Re: [mpls-linux-general] How ldp assigns labes

[Dragoescu A. <dra...@gm...>]

does ldp implementation support loop detection?

On 6/23/07, Marco Schmidt <mar...@s2...> wrote:
>
> You mean a setup like this?
>
>   ---B---
>       /         \
>     A< >D
>       \         /
>   ---C---
>
> This scenario doesn't work since you change the link cost (in OSPF) on one
> link. The LDP-implementation doesn't support equal cost multipaths
> (ECMPs).
>
> Routes are redistributed by the zebra routing manager, you may look at the
> resources of quagga.net to see how the protocol deamons interact with
> each other.
>
> >
> >
> >
> > Hy,
> >
> >
> >
> > I have a question ? How ldp assigns labels.Have this setup:
> >
> >
> >
> > B    AD
> >
> >
> >
> >
> >
> > A connected with B and C and D also
> >
> > Ok,after ospf will distribute routes , how ldo assigns labels.
> >
> > On LSR A Ospf will distribute 2 routes with destination D.
> >
> > LDP will create 2 LSP with destination D ?
> >
> >
> >
> > As implementation how LDP will assign labes? It looks on ospf
> > routing table and for any destination will assign a new label?
> >
> >
> >
> > 10x,
> >
> > AlexD
> >
> >
> >
>
> --
> Marco Schmidt
> mailto:mar...@s2...
>
>
>


-- 
Alexandru Dragoescu
dra...@gm...
QA engineer
ITCNETWORKS Romania

Re: [mpls-linux-general] How ldp assigns labes

[Dragoescu A. <dra...@gm...>]

On 6/23/07, Marco Schmidt <mar...@s2...> wrote:
>
> You mean a setup like this?
>
>   ---B---
>       /         \
>     A< >D
>       \         /
>   ---C---


ok with this setup , ospf will distribute 2 routes with destination router D
and will mark one of them as the best.If i send mpls trafic to router D ,
that traffic will follow that route let's say trough router B.My question
is ,  if disconnect one link of router B , after a while traffic will be
sent trough router C?
10x

-- 
Alexandru Dragoescu
dra...@gm...
QA engineer
ITCNETWORKS Romania