`{Itust A
`\olupe
`
`ea)
`The B pe
`
`Loole
`
`Oat
`
`e
`ea
`Le)
`
`2o
`
`e
`eS
`
`a a (
`
`Ss
`
`< a
`
`z,
`
`a= F
`
`a)
`a)
`Sp
`aa
`
`aT
`
`ar
`
`4>
`
`)
`oe
`<i
`
`=N
`
`nai
`
`me
`aa
`
`5]
`ZO
`
`OU12
`
`
`
`UNIX is a technology trademark of X/Open Company,Ltd.
`
`The publisher offers discounts on this book when ordered in quantity for specialsales.
`For more information please contact:
`Corporate & Professional Publishing Group
`Addison-Wesley Publishing Company
`One Jacob Way
`Reading, Massachusetts 01867
`
`Library of Congress Cataloging-in-Publication Data
`Stevens, W. Richard
`TCP/IP Illustrated: the protocols/W. Richard Stevens.
`p. cm. — (Addison-Wesley professional computingseries)
`Includes bibliographical references andindex.
`ISBN 0-201-63346-9 (v. 1)
`1,TCP/IP (Computer networkprotocol)I. Title. II. Series.
`TK5105.55574 1994
`004.6°2—de20
`
`Copyright © 1994 Addison Wesley Longman,Inc.
`
`All rights reserved. No part of this publication may be reproduced,stored in a retrieval system,
`or transmitted in any form or by any means, electronic, mechanical, photocopying, recording,or
`otherwise, without prior written permission of the publisher. Printed in the United States of
`America. Published simultaneously in Canada.
`
`Text printed on recycled and acid-free paper
`ISBN 0-201-63346-9
`
`10111213141516 MA 00 99 98 97
`
`10th Printing July, 1997
`
`
`
`
`TCP: Transmission Control Protocol
`Chapter17
`
`Each TCP segmentcontains the source and destination port number to identify the
`sending and receiving application. These two values, along with the source and desti-
`
`fies each TCP connection in an internet.
`The sequence numberidenti
`
`chapter where we'll see that the FIN flag consumes a sequence numberalso.)
`Since every byte thatis exchanged is numbered, the acknowledgment number contains
`This is therefore the Sequence number plus 1 of the last successfully received byte af
`data. This field is valid only if the ACK flag (described below)is on.
`Sending an ACK costs nothing because the 32-bit acknowledgment numberfield Ss
`always part of the header, as is the ACK flag. Therefore we'll see that once a connection
`is established,this field is alwaysset and the ACK flag is alwayson.
`be flowing in each direction, independentof the other direction. Therefore, each end =
`a connection must maintain a sequence numberof the data flowing in each direction.
`TCP can be described as a sliding-window protocol withoutselective or negative
`acknowledgments.
`(The sliding window protocol used for data transmission =
`described in Section 20.3.) We say that TCP lacks selective acknowledgments because
`the acknowledgment numberin the TCP headermeansthat the senderhas successfull
`received up through but not including that byte. There is currently no way to acknowl
`edge selected pieces of the data stream. For example,if bytes 1-1024 are received OK,
`and the next segment contains bytes 2049-3072, the receiver cannot acknowledge this
`
`The header length gives the length of the headerin 32-bit words. This is requissdl
`because the length of the optionsfield is variable. With a 4-bit field, TCPis limited wa
`60-byte header. Without options, however, the normalsize is 20 bytes.
`
`=
`
`
Accessing this document will incur an additional charge of $.
After purchase, you can access this document again without charge.
Accept $ Charge
Still Working On It
This document is taking longer than usual to download. This can happen if we need to contact the court directly to obtain the document and their servers are running slowly.
Give it another minute or two to complete, and then try the refresh button.
A few More Minutes ... Still Working
It can take up to 5 minutes for us to download a document if the court servers are running slowly.
Thank you for your continued patience.
This document could not be displayed.
We could not find this document within its docket. Please go back to the docket page and check the link. If that does not work, go back to the docket and refresh it to pull the newest information.
Your account does not support viewing this document.
You need a Paid Account to view this document. Click here to change your account type.
Your account does not support viewing this document.
Set your membership
status to view this document.
With a Docket Alarm membership, you'll
get a whole lot more, including:
- Up-to-date information for this case.
- Email alerts whenever there is an update.
- Full text search for other cases.
- Get email alerts whenever a new case matches your search.
One Moment Please
The filing “” is large (MB) and is being downloaded.
Please refresh this page in a few minutes to see if the filing has been downloaded. The filing will also be emailed to you when the download completes.
Your document is on its way!
If you do not receive the document in five minutes, contact support at support@docketalarm.com.
Sealed Document
We are unable to display this document, it may be under a court ordered seal.
If you have proper credentials to access the file, you may proceed directly to the court's system using your government issued username and password.
Access Government Site
