Re: cleaned up question sheet

[Jim Boyle <jimpb@nc.rr.com>]

I think the plan is for any/all of us to answer these by today-ish, using
whatever resources we have at our command, and then we were going to
discuss and try to extract the essential requirements from the mix.  At
least that was the gameplan.  today-ish in ietf time might take a week or
so though.  Definitely the plan was to kick up the heat this week on this
mailing list, and I suppose 3 messages is hotter than 1.

What are your thoughts on how we proceed?

Jim

On Tue, 3 Jul 2001, Rob Coltun wrote:

> Thanks Jim - is there a game plan from this point moving forward?
>
> thanks,
> ---rob
>
> Jim Boyle wrote:
>
> > took a pass at cleaning up the question sheet, no new content.
> >
> > ------* snip here *--------
> > A. Definitions
> >
> > 1. In determining the specific requirements, the design team should
> >    precisely define  the concepts "survivability", "restoration",
> >    "protection", "protection switching", "recovery", "re-routing"
> >    etc. and their relations. This would enable the requirements doc to
> >    describe precisely which of these will be addressed.
> >
> >    In the following, the term "restoration" is used to indicate the broad
> >    set of policies and mechanisms used to ensure survivability.
> >
> > B. Network types and protection modes
> >
> > 1. What is the scope of the requirements with regard to the types
> >     of networks covered? Specifically, are the following in scope:
> >
> >     -  Restoration of connections in mesh optical networks
> >        (opaque or transparent)
> >     -  Restoration of connections in hybrid mesh-ring networks
> >     -  Restoration of LSPs in MPLS networks (composed of LSRs overlaid on a
> >        transport network, e.g., optical)
> >     -  Any other types of networks?
> >     -  Is commonality of approach, or optimization of approach more important?
> >
> > 2.  What are the requirements with regard to
> >      the protection modes to be supported in each network type covered?
> >      (Examples of protection modes include 1+1, M:N, shared mesh,
> >      UPSR, BLSR, newly defined modes such as P-cycles, etc.)
> >
> > 3.  What are the requirements on local span (i.e., link by link)
> >      protection and end-to-end protection, and the interaction between them?
> >      E.g.: what should be the granularity of connections for
> >      each type (single connection, bundle of connections, etc).
> >
> > C. Hierarchy
> >
> > 1. Vertical (between two network layers):
> >     What are the requirements for the interaction between restoration
> >     procedures across two network layers, when these features are
> >     offered in both layers?
> >     (Example, MPLS network realized over pt-to-pt
> >     optical connections.) Under such a case,
> >
> >     (a) Are there any criteria to choose which layer should provide
> >           protection?
> >
> >     (b) If both layers provide survivability features, what are the
> >           requirements to coordinate these mechanisms?
> >
> >     (c) How is lack of current functionality of cross-layer
> >           cooridnation currently hampering operations?
> >
> >     (d) Would the benefits be worth additional complexity associated
> >           with routing isolation (e.g. VPN, areas), security, address
> >           isolation and policy / authentication processes?
> >
> > 2. Horizontal (between two areas or administrative subdivisions within
> >     the same network layer):
> >
> >     (a) What are the criteria that trigger the creation of protocol or
> >           administrative boundaries pertaining to restoration? (e.g.,
> >           scalability?  multi-vendor interoperability? what are the
> >           practical issues?)  multi-provider? Should multi-vendor
> >           necessitate hierarchical seperation?
> >
> >     When such boundaries are defined:
> >
> >     (b) What are the requirements on how protection/restoration is
> >           performed end-to-end across such boundaries?
> >
> >     (c) If different restoration mechanisms are implemented on two
> >           sides of a boundary, what are the requirements on their
> >           interaction?
> >
> >    What is the primary driver of horizontal hierarchy? (select one)
> >     - functionality (e.g. metro -v- backbone)
> >     - routing scalability
> >     - signalling scalability
> >     - current network architecture, trying to layer on TE ontop of
> >       already hiearchical network architecture
> >     - routing and signalling
> >
> >    For signalling scalability, is it
> >     - managability
> >     - processing/state of network
> >     - edge-to-edge N^2 type issue
> >
> >     For routing scalability, is it
> >     - processing/state of network
> >     - are you flat and want to go hierarchical
> >     - or already hierarchical?
> >     - data or TDM application?
> >
> > D. Policy
> >
> > 1. What are the requirements for policy support during
> > protection/restoration,
> >     e.g., restoration priority, preemption, etc.
> >
> > E. Signaling Mechanisms
> >
> > 1. What are the requirements on the signaling transport mechanism
> >    (e.g., in-band over sonet/sdh overhead bytes, out-of-band over
> >    an IP network, etc.) used to communicate restoration protocol
> >    messages between network elements. What are the bandwidth and
> >    other requirements on the signaling channels?
> >
> > 2. What are the requirements on fault detection/localization mechanisms
> >    (which is the prelude to performing restoration procedures)
> >    in the case of opaque and transparent optical networks?
> >    What are the requirements in the case of MPLS restoration?
> >
> > 3. What are the requirements on signaling protocols to be used in
> >    restoration procedures (e.g., high priority processing, security, etc).
> >
> > 4. Are there any requirements on the operation of restoration protocols?
> >
> > E. Quantitative
> >
> > 1. What are the quantitative requirements (e.g., latency) for completing
> >    restoration under different protection modes (for both local and
> >    end-to-end protection)?
> >
> > F. Management
> >
> > 1. What information should be measured/maintained by the control plane at
> >     each network element pertaining to restoration events?
> >
> > 2. What are the requirements for the correlation between control plane
> >     and data plane failures from the restoration point of view?
>