kaba@acdhq.north.de (Kai Bartels) (02/27/91)
Hi!
Sending a SYN advances the sequence number by one since it must be ACKed.
A FIN is ACKed, too, so does it advanced the sequence number?
I browsed through RFC761 but found nothing which tells me. :-(
"Is there anybody out there" (who knows about it) ?
greetings, Kai
--------------------
Kai Bartels | kaba@acdhq.UUCP | The sound of bombs
Hudemuehler 37 | kaba@acdhq.north.de | Has given way to childrens cries
D-2800 HB 41 | G14B@DHBRRZ41.BITNET | <Fischer-Z>
(0421)34636-13 |g14b@sie.rz.uni-bremen.de|------------------------------
bang: {uunet|pyramid|rutgers}!cbmvax!cbmehq!cbmger!acdhq!kaba
--
--------------------
ACD Advanced Computer Design GmbH |acdhq.uucp |Networks
Dammweg 15 | Tel.: (+49) (0) 421 34636-0| | and
D2800 Bremen 1 | Fax : (+49) (0) 421 3499518|...!cbmvax!cbmger!acdhq| more!solensky@animal.clearpoint.com (Frank T. Solensky) (03/03/91)
>Hi! >Sending a SYN advances the sequence number by one since it must be ACKed. >A FIN is ACKed, too, so does it advanced the sequence number? >I browsed through RFC761 but found nothing which tells me. :-( Kai -- RFC 791 (which updated 763) describes the closing sequence pretty well and illustrates this case in Figure 13 (page 39). The packet that ACKs the FIN will have an ACK number one greater than the FIN's sequence number. So, yes, the sequence number is incremented after the FIN is transmitted (so that ACK will == snd.NXT). You may want to also get a copy of RFC-1122 (Requirements for Internet hosts): this document clarifies a number of points in both the TCP and IP protocol specifications that have been interpreted in different (and frequently incompatible) ways. -- Frank Solensky / Clearpoint Research Corp.
kaba@acdhq.north.de (Kai Bartels) (03/11/91)
> >Hi! Hi! > Kai -- > RFC 791 (which updated 763) describes the closing sequence pretty > well and illustrates this case in Figure 13 (page 39). The packet that ACKs > the FIN will have an ACK number one greater than the FIN's sequence number. > So, yes, the sequence number is incremented after the FIN is transmitted > (so that ACK will == snd.NXT). > You may want to also get a copy of RFC-1122 (Requirements for Internet > hosts): this document clarifies a number of points in both the TCP and IP > protocol specifications that have been interpreted in different (and frequently > incompatible) ways. Thanks a lot! This rfc1122 is really great! I think it'll help me with a bunch (spelling?) of problems in the future. > -- Frank Solensky / Clearpoint Research Corp. greetings, Kai -------------------- Kai Bartels | kaba@acdhq.UUCP | The sound of bombs Hudemuehler 37 | kaba@acdhq.north.de | Has given way to childrens cries D-2800 HB 41 | G14B@DHBRRZ41.BITNET | <Fischer-Z> (0421)34636-13 |g14b@sie.rz.uni-bremen.de|------------------------------ bang: {uunet|pyramid|rutgers}!cbmvax!cbmehq!cbmger!acdhq!kaba