Avocent Access Router Cyclades-PR2000 Manual do Utilizador descarregar pdf (Página 109)

109

Cyclades-PR2000

Chapter 12 - Filters and Rules

An example showing the third type of traffic control is given in Figure 12.8. The network administrator wants to

prioritize the access to his web server. He also wants to prioritize e-mail sent by his SMTP server, but the

priority should be lower. All other traffic should have the lowest priority. For web server access, the important

flow direction is not the user requests, but rather the data requested. The traffic control rule must be placed on

link 2. In the case of e-mail, the important flow is the data leaving the e-mail server, and not the

acknowledgements back. This is also governed by link 2. (Note: flow control could be placed on the data

request packets and the SMTP acknowledgements by associating rules to link 1.)

Web Server

E-mail Server

Web Client

E-mail Server

PR2000

Requests

ACKs Back

Data Requested

E-mail out

Port: 80

Port: 25 (SMTP)

Port: Any

Link 2

Link 1

Port: Any

INTERNET

FIGURE 12.9 TRAFFIC RULE EXAMPLE 2

1 2 ... 104 105 106 107 108 109 110 111 112 113 114 ... 135 136

Sem comentários

Avocent Access Router Cyclades-PR2000 Manual do Utilizador Página 109