On 06/12/2018 00:34, Brian E Carpenter wrote:
Of course here it is only looking for two values
(TCP or UDP).
You too just killed SCTP ;-)
Well the last time I heard about SCTP was when we were forced to include
it as an option for IPFIX.
How much SCTP exists in the real world?
If it has to look at any it has a much more complex set of tests, or a
large vector table given the way the EH space is fragmented.
Frankly doing it without a network processor seems wrong. You can't expect
an ASIC or FPGA based device to handle the EH structures.
Something that has served the IETF well over the years is not to
constrain the forwarding
implementation, and I think we would be wise to continue in that mould.
Also we need
to remember that an NP is an application specific processor, and thus
has various
hardware assists.
No one talks about the internals of an NP, and I am not current on any
vendor's design,
but it is reasonable to suggest that in addition to the s/w parser there
might
be a h/w parser that does the heavy lifting, i.e. if IPv6 packet of
expected type, dec
TTL and do what the TCAM say picking this ECMP option else parse it the
hard way.
Then there is something that we do not talk at all about in such
designs: electrical power.
There is no question that it takes more power to s/w parse a packet, and
sooner of later
the power burn of the Internet is going to come under scrutiny, and we
will be asked
to reduce its carbon footprint.
- Stewart
- Stewart
