[ih] Correct name for early TCP/IP working group?
Brian E Carpenter
brian.e.carpenter at gmail.com
Sun Feb 2 18:55:33 PST 2025
On 29-Jan-25 01:06, Scott Bradner wrote:
> ps - you can find the paper on Kleinrock's website
>
> https://www.lk.cs.ucla.edu/data/files/Kamoun/Data%20Communications%20through%20Large%20Packet-Switching%20Networks.pdf
>
>> On Jan 28, 2025, at 6:55 AM, Scott Bradner via Internet-history <internet-history at elists.isoc.org> wrote:
>>
>> fwiw - the 1976 Kleinrock & Kamoun paper "Hierarchical Routing for Large Networks, Performance evaluation and optimization" is all about scaling of packet switched networks
Thanks. I got round to reading this again today (I'm pretty sure I read it ~45 years ago). Yes, it's all about scaling of the routing system, thereby limiting routing state, but what I think we were discussing here was avoiding flow state. Of course that's why packet switching scales and virtual circuits don't.
Incidentally, that's why Bell Canada had the first viable X.25 offering in ~1976: its core was a datagram network, not a virtual circuit network, because it was designed by Peter Cashin, an alumnus of the NPL team. (See my interview with Peter that I mentioned a while back [1].)
Brian
[1] https://www.cs.auckland.ac.nz/research/groups/CDMTCS/researchreports/download.php?selected-id=884
>>
>> Scott
>>
>>
>>
>>> On Jan 27, 2025, at 8:47 PM, Brian E Carpenter via Internet-history <internet-history at elists.isoc.org> wrote:
>>>
>>> Vint, and Noel,
>>>
>>> I just glanced through Baran's 1964 paper, and it clearly recognized
>>> statelessnesss (and a standard packet header) as important for network
>>> survivability and adaptive routing. But although he mentions networks
>>> of intercontinental size, I didn't spot any discussion of scalability
>>> as such.
>>>
>>> Interestingly, exactly the same applies to Dave Clark's 1988 "Design
>>> Philosophy" paper.
>>>
>>> In RFC 1958, we did note as principle 3.3 that "All designs must scale
>>> readily to very many nodes per site and to many millions of sites".
>>> I guess that by then (1996) this was too obvious to ignore, and it was
>>> written when IPv4 address exhaustion was considered inevitable.
>>>
>>> Maybe somebody who knows the early literature better than me can find
>>> something. But it's almost as if the intrinsic scalability of stateless
>>> packet switching was an unnoticed and accidental property.
>>>
>>> Regards
>>> Brian
>>>
>>> On 27-Jan-25 11:16, Vint Cerf via Internet-history wrote:
>>>> statelessness was an important design choice and was made consciously so
>>>> that paths were not critical to successful transport. For example we did
>>>> not want to have to reassemble along a particular path. Even though we
>>>> deprecated fragmentation, at the time we thought it was important, we did
>>>> not want gateway (router) state to be necessary to accomplish reassembly
>>>> regardless of path. I don't know that we recognized the scalability aspect
>>>> but we definitely cared a lot about statelessness of the gateways.
>>>> v
>>>> On Sun, Jan 26, 2025 at 4:25 PM Noel Chiappa via Internet-history <
>>>> internet-history at elists.isoc.org> wrote:
>>>>>> From: Jack Haverty jack at 3kitty.org
>>>>>
>>>>>> At the time, the "ARPANET crowd" was skeptical that the "datagram"
>>>>>> nature of TCP could be made to work. Traditional networks, including
>>>>>> the ARPANET, had elaborate internal mechanisms to provide a "virtual
>>>>>> circuit" service to its users.
>>>>>
>>>>> I was thinkking about this, and wondering if internetworking was a more
>>>>> fundamental advance than the ARPANET (relegating the latter to a
>>>>> 'ground-breaking experiment'), and I had another thought.
>>>>>
>>>>>
>>>>> Internetworking (following in the track of CYCLADES) made much of the
>>>>> fate-sharing aspect - that the data needed to ensure reliable transmission
>>>>> was co-located was the application. One good reason for that (that we knew
>>>>> at
>>>>> the time) was that it made the network itself simpler.
>>>>>
>>>>> But there's another side to that, one that was even more important, and
>>>>> which
>>>>> I'm not sure was obvious to us at the time (1977-79), which is that because
>>>>> it means the intermediate packet switches in the overall internet carry no
>>>>> state about the connections travelling through them, there's no scaling
>>>>> limit. This, to me, has been the single biggest reason why the Internet has
>>>>> been able to grow to the stupendous size it has.
>>>>>
>>>>> I don't think we could have been thinking 'this aspect of lack of state in
>>>>> the internet packet switches neans it will scale indefinitely', because I
>>>>> don't think we had any idea, at that point, about how to do path selection
>>>>> in
>>>>> a global-scale internet - so global-scale internets could not have been in
>>>>> our thinking.
>>>>>
>>>>> Did that infinite scalability turn out to be just a happy accident, a
>>>>> side-effect of good fundamental design (but one whose true complete value
>>>>> wasn't obvious to us at the time), one that moved state out of the internet
>>>>> packet switches?
>>>>>
>>>>> Noel
>>>>> --
>>>>> Internet-history mailing list
>>>>> Internet-history at elists.isoc.org
>>>>> https://elists.isoc.org/mailman/listinfo/internet-history
>>>>>
>>> --
>>> Internet-history mailing list
>>> Internet-history at elists.isoc.org
>>> https://elists.isoc.org/mailman/listinfo/internet-history
>>
>> --
>> Internet-history mailing list
>> Internet-history at elists.isoc.org
>> https://elists.isoc.org/mailman/listinfo/internet-history
>
More information about the Internet-history
mailing list