Your host in this example has IP address 172.16.1.1. Someone tries to send e-mail from a remote host with IP address 192.168.3.4. If successful, this will generate an SMTPdialogue, consisting of SMTP commands and mail, between the remote user and the SMTP server on your host. Assume that a user on your host tries to send packets for thisscenario as shown:Scenario Direction Src Addr Dest Addr Protocol Dest Port Action12InOut192.168.3.4 172.16.1.1172.16.1.1 192.168.3.4Indicate which packets are permitted or deTCPTCP251234??and which rule is used in each case. Rule Direction Src Addr Dest Addr Protocol Dest Port ActionABсDEInOutOutInEitherExternalInternalInternalInternalAnyExternalExternalExternal InternalAnyTCPTCPTCPTCPAny25> 102325> 1023AnyPermitPermitPermitPermitDeny

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Your host in this example has IP address 172.16.1.1. Someone tries to send e-mail from a remote host with IP address 192.168.3.4. If successful, this will generate an SMTP dialogue, consisting of SMTP commands and mail, between the remote user and the SMTP server on your host. Assume that a user on your host tries to send packets for this scenario as shown: Scenario Direction Src Addr 1 2 In Out Dest Addr 192.168.3.4 172.16.1.1 Protocol Dest Port Action TCP 172.16.1.1 192.168.3.4 TCP 25 1234 ? ? Indicate which packets are permitted or denied, and which rule is used in each case.

Your host in this example has IP address 172.16.1.1. Someone tries to send e-mail from a remote host with IP address 192.168.3.4. If successful, this will generate an SMTP dialogue, consisting of SMTP commands and mail, between the remote user and the SMTP server on your host. Assume that a user on your host tries to send packets for this scenario as shown: Scenario Direction Src Addr 1 2 In Out Dest Addr 192.168.3.4 172.16.1.1 Protocol Dest Port Action TCP 172.16.1.1 192.168.3.4 TCP 25 1234 ? ? Indicate which packets are permitted or denied, and which rule is used in each case.

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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