Ericsson EDN312 Guia do Utilizador descarregar pdf (Página 23)

Function Description

4/1553-HSC 901 101/2 Uen B 2009-02-27

ensure that the IP DSLAM will always be able to start. Optimizing for

robustness will result in longer startup time. Both the Boot SW and the

Application SW can run the DHCP procedure. Under normal network

conditions, it will always be the Boot SW that runs the DHCP procedure

during startup. The Application SW will only run the procedure if there is no

reply for over four minutes during startup, or after the IP DSLAM is running

with the application SW (when the DHCP lease expires). Figure 10 on page

19 illustrates the DHCP procedure. Note that the procedure also

accommodates Dynamic Management VLAN (DMV) that also uses

untagged traffic. For more information about how the DMV works, please

refer to Dynamic Management VLAN Configuration Guide.

Send tagged DHCP request

IP DSLAM Runs ManagedIP DSLAM runs Unmanaged

Use IP Address from DHCP

Send untagged DHCP request

DHCP Response

received?

Yes No

DHCP Response

received?

Yes

DHCP Response

Valid?

Yes

Timeout

2 min.

Timeout

2 min.

Change Management VLAN ID

Retrieve Management VLAN ID

from flash

Normal Start-up

Figure 10 DHCP Procedure

In normal network conditions (all network resources are available) the IP

DSLAM will immediately receive a legal DHCP response. After validating

the legality (format) of the response the IP DSLAM will use the received

parameters and proceed with the startup procedure. The procedure always

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 51 52

Sem comentários

Ericsson EDN312 Guia do Utilizador Página 23