Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!uunet!pdn!larry
From: larry@pdn.paradyne.com (Larry Swift)
Newsgroups: comp.dcom.lans
Subject: Re: What services does X.25 provide?
Keywords: x.25, services, login, e-mail, file transfer, IPC
Message-ID: <6624@pdn.paradyne.com>
Date: 2 Oct 89 12:43:54 GMT
References: <796@maxim.erbe.se> <3279@wasatch.utah.edu> <522@wet.UUCP> <1989Sep18.020822.16329@cit5.cit.oz> <22877@cos.com>
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Reply-To: larry@pdn.paradyne.com (Larry Swift)
Organization: AT&T Paradyne, Largo, Florida
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In article <22877@cos.com> howard@cos.com (Howard C. Berkowitz) writes:
>The second is one way to provide the Connectionless Network Service
>(CLNS); it uses X.25 to provide a technology-specific interface
>to a packet-switching network, but the service interface shown to Transport
>is connectionless, based on the OSI Internet Protocol (ISO 8473).

This description seems to be implying a reason for this interface,
but if so, it escapes me.  Can you provide some background as to why
network designers might want a CNLS interface over an inherently
connection-oriented network layer?  If the Layer 3 path traversed
multiple subnets with an unreliable segment such as X.25-Ethernet-X.25,
is the CNLS interface to Layer 4 no less viable than the CONS?  Is it
simply easier to use?  What else?


Larry Swift                     larry@pdn.paradyne.com
AT&T Paradyne, LG-132           Phone: (813) 530-8605
8545 - 126th Avenue, North
Largo, FL, 34649-2826           She's old and she's creaky, but she holds!