DGS-3700-12/DGS-3700-12G Series Layer 2 Gigabit Ethernet Switch User Manual
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Simply put, D-Link Single IP Management is a concept that will stack switches togeth er over Eth ernet inste ad of using
stacking ports or modules. There are some advantages in implementing the "Single IP Management" feature:
1. SIM can simplify management of small workgroups or wiring c losets while scaling the network to handle
increased bandwidth demand.
2. SIM can reduce the number of IP address needed in your network.
3. SIM can eliminate any specialized cables for stacking connectivity and remove the distanc e barriers that
typically limit your topology options when using other stacking technology.
Switches using D-Link Single IP Management (labeled here as SIM) mus t conform to the following rules:
SIM is an optional feature on the Switch and can easily be enabled or disabled through the C ommand Line Interf ace
or Web Interface. SIM grouping has no effect on the normal operation of the S witch in the user's network.
There are three classifications for SIM. The Commander Switch (CS), which is the m aster switch of the group,
Member Switch (MS), which is a switch that is recognized by the CS a member of a SIM group, and a Candidate
Switch (CaS), which is a Switch that has a physical link to the SIM group but has not been recogn i zed b y the CS as a
member of the SIM group.
A SIM group can only have one Commander Switch (CS).
All switches in a particular SIM group must be in the same IP subnet ( broadcast domain). Mem bers of a SIM gro up
cannot cross a router.
A SIM group accepts up to 33 switches (numbered 0-32), including the Comm ander Switch (numbered 0).
There is no limit to the number of SIM groups in the same IP subnet (broadcas t dom ain), ho wever a single s witch c an
only belong to one group.
If multiple VLANs are configured, the SIM group will only utilize the system VLAN on any switch.
SIM allows intermediate devices that do not support SIM. This enables the use r to manage switches that are m ore
than one hop away from the CS.
The SIM group is a group of switches that are managed as a single entit y. SIM switches m ay take on thr ee different
roles:
1. Commander Switch (CS) – This is a switch that has been manually configured as the contro ll ing d evic e f or a
group, and takes on the following characteristics:
It has an IP Address.
It is not a commander switch or member switch of another Single IP group .
It is connected to the member switches through its management VLAN.
2. Member Switch (MS) – This is a switch that has joined a single I P group and is accessible from the CS, and it
takes on the following characteristics:
It is not a CS or MS of another Single IP group.
It is connected to the CS through the CS management VLAN.
3. Candidate Switch (CaS) – This is a switch that is ready to join a SI M group but is not yet a member of the
SIM group. The Candidate Switch may join the SIM group of a switch by manually conf iguring it to be a MS of
a SIM group. A switch configured as a CaS is not a member of a SIM group a nd will take on the following
characteristics:
It is not a CS or MS of another Single IP group.
It is connected to the CS through the CS management VLAN
After configuring one switch to operate as the CS of a SIM group, additional switches may join the group t hrough a
direct connection to the Commander switch. Only the Commander switch will allow entry to the candidate switch
enabled for SIM. The CS will then serve as the in band entry point for access to the MS. The CS's IP address will
become the path to all MS's of the group and the CS's Administrator's password, and/ or authentication will control
access to all MS's of the SIM group.
With SIM enabled, the applications in the CS will redirect the packet ins tead of executing the packets. The
applications will decode the packet from the administrator, modif y some dat a, the n send it t o the MS. After execution ,
the CS may receive a response packet from the MS, which it will encode an d send it back to the administrator.
When a CS becomes a MS, it automatically becomes a member of the fir st SNMP c omm unity (include r ead/writ e and
read only) to which the CS belongs. However, if a MS has its own IP addr ess, it c an belong to SNM P communit ies to
which other switches in the group, including the CS, do not belong.