Suppose TCP is used over a lossy link that loses on average one segment in four. Assume the delay x bandwidth window size is considerably larger than four segments. (a) What happens when we start a connection? Do we ever get to the linear-increase phase of congestion avoidance? (b) Without using an explicit feedback mechanism from the routers, would TCP have any way to distinguish such link losses from congestion losses, at least over the short term? (c) Suppose TCP senders did reliably get explicit congestion indications from routers. Assuming links as above were common, would it be feasible to support window sizes much larger than four segments? What would TCP have to do?

Suppose TCP is used over a lossy link that loses on average one segment in four. Assume the delay x bandwidth window size is considerably larger than four segments. (a) What happens when we start a connection? Do we ever get to the linear-increase phase of congestion avoidance? (b) Without using an explicit feedback mechanism from the routers, would TCP have any way to distinguish such link losses from congestion losses, at least over the short term? (c) Suppose TCP senders did reliably get explicit congestion indications from routers. Assuming links as above were common, would it be feasible to support window sizes much larger than four segments? What would TCP have to do?

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Suppose TCP is used over a lossy link that loses on average one segment in four. Assume the delay x bandwidth window size is considerably larger than four segments. (a) What happens when we start a connection? Do we ever get to the linear-increase phase of congestion avoidance? (b) Without using an explicit feedback mechanism from the routers, would TCP have any way to distinguish such link losses from congestion losses, at least over the short term? (c) Suppose TCP senders did reliably get explicit congestion indications from routers. Assuming links as above were common, would it be feasible to support window sizes much larger than four segments? What would TCP have to do?