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RE: [PWE3] PWE Service interworking
thanks for the feedback Jack and understood.
Quick question, when you say service interworking
between ATM-CES, I an not quite sure what that means,
does that mean ATM to TDM or non AAL1 ATM to AAL1 ATM?
Thanks,
Mark
--- Jack Pugaczewski <jtpugac@qwest.com> wrote:
> A carrier's perspective:
>
> The existing customer based is a combination of the
> following Networking
> Interworking options:
> ATM-ATM, FR-FR, CE-CE, Ethernet-Ethernet
>
> and Service Interworking Options:
> ATM-FR, ATM-CES
>
> A major purpose for moving to a converged MPLS (or
> PWE-3) network is to take
> all of this functionality with as well a have the
> ability to introduce new
> services (MPLS, IP,...). This functionality must
> bring with it the OAM
> fault and performance functionality that allows
> carriers to use the
> combination of PE, CE and element management systems
> to perform fault
> localization.
>
> Specifications such as FRF.5 and FRF.8 are clearly
> defined and this same
> approach should be used int the PWE3 space.
>
> Respectfully,
>
> Jack
>
> PJMWBGJJREGTATALDBJHJHSLDHGSDWJAMY
>
>
> F
> > -----Original Message-----
> > From: pwe3-admin@ietf.org
> [mailto:pwe3-admin@ietf.org]On Behalf Of Mark
> > Seery
> > Sent: Tuesday, June 03, 2003 11:01 PM
> > To: pwe3@ietf.org
> > Subject: Re: [PWE3] PWE Service interworking
> >
> >
> > So having tried a general description, a slightly
> > (not constructing access points etc.) treatment of
> > this issue might look something like the
> following.
> >
> > Acronyms NIWF - network internetworking function
> and
> > SIWF - Service interworking function are not
> acronyms
> > used by any standards body (that I know of).
> >
> > fig.1 is essentially how I think of PW today.
> >
> > Network Interworking
> > ====================
> > fig.1
> >
> > CE1 PE1 P PE2 CE2
> > ----------- -----------
> > | NIWF | | NIWF |
> > ------ |---------| ------ |---------| ------
> > | FR |--| FR | PW |---| PW |---| PW | FR |--| FR |
> > ------ ----------- ------ ----------- ------
> >
> > Where FR could be FR, Ethernet, or ATM.
> > In the ATM case, AAL5 would (typically) be
> > encapsulated on to a PW, and no understanding of
> upper
> > layer protocols would be required.
> >
> > Service Interworking
> > ====================
> > fig.2
> >
> > CE1 PE1 P PE2 CE2
> > ----------- -----------
> > | SIWF | | |
> > ------ |---------| ------ | | ------
> > | FR |--| FR | PW |---| PW |---| PW |--| PW |
> > ------ ----------- ------ ----------- ------
> >
> > The scenario of a PW going to a CE is unlikely
> today,
> > of course, but shown here as a theoretical option.
> >
> > or
> > fig.3
> >
> > CE1 PE1 P PE2 CE2
> > ----------- -----------
> > | SIWF | | |
> > ------ |---------| ------ | | ------
> > | FR |--| FR | MP |---| MP |---| MP |--| MP |
> > ------ ----------- ------ ----------- ------
> >
> > The scenario of a MPLS (MP) service going to a CE
> is
> > more likely than that of a PW, but still not
> likely to
> > be widespread in the near term
> >
> > or
> > fig.4
> >
> > CE1 PE1 P PE2
> CE2
> > ----------- -----------------
> > | NIWF | | NIWF | SIWF |
> > ------ |---------| ------ |---------------|
> > -----
> > | FR |--| FR | PW |---| PW |---| PW | FR | ATM
> > |--|ATM|
> > ------ ----------- ------ -----------------
> > -----
> >
> > In this scenario FR is encapsulated on to a PW at
> PE1
> > and decapsulated off of a PW at PE2 and then
> service
> > interworked to an ATM service. The ATM service may
> be
> > going to a CE or to an ATM network (in which case
> the
> > SIWF would be slightly different)
> >
> > or
> > fig.5
> >
> > CE1 PE1 P PE2 CE2
> > ----------- -----------
> > | SIWF | | SIWF |
> > ------ |---------| ------ |---------| ------
> > | FR |--| FR | PW |---| PW |---| PW | ATM|--| ATM|
> > ------ ----------- ------ ----------- ------
> >
> > this seems simpler than some of the previous
> examples
> > but might actually be quite hard and is where
> > translation to from PW encaps would need to be
> pretty
> > good (my guess).
> >
> > or
> > fig.6
> >
> > CE1 FR SW ATM SW PE1 P
> > ----------- -----------
> > | SIWF | |NIWF/SIWF|
> > ------ |---------| ------- | --------|
> ------
> > | FR |--| FR | ATM|---| ATM |---| ATM | MP|--| MP
> |
> > ------ ----------- ------- -----------
> ------
> >
> > In this case FR is interworked with ATM, and RFC
> 1490
> > with RFC 1483 at the FR SW. Then at the PE, ATM is
> > network or service interworked with MP. In the
> case of
> > routed RFC 1490/1483, an IP packet could be popped
> and
> > encapsulated over MPLS, but there would still be
> OAM
> > interworking between the ATM and MPLS functions.
> >
> > In the case of bridged RFC1490/1483, it may be
> > possibly to interwork the ATM and MPLS functions
> and
> > then interwork RFC1483 and PW.
> >
> > Just some ideas of scenarios we may be looking at
> in
> > the future.
> >
> > Having thought about it, there is probably no
> getting
> > by with just a casual discussion of this issue. So
> we
> > either add it to the charter now, or delay it as
> seems
> > to be the consensus (i.e. I have only heard one
> strong
> > voice pushing it to the forefront).
> >
> > Mark
> >
> >
> > _______________________________________________
> > pwe3 mailing list
> > pwe3@ietf.org
> > https://www1.ietf.org/mailman/listinfo/pwe3
> >
>
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