Media5 Mediatrix 4104, Reference Manual

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VLAN Reference Manual (SIP Version)
Mediatrix 4104 339
4. Restart the Mediatrix 4104 so that the changes may take effect.
Ethernet Frames Issue
There is currently an issue with the CPU of the Mediatrix 4104. This issue prevents Ethernet frames, which
have a 802.1q tag, to be correctly forwarded through the
ETH2 (LAN) port of the Mediatrix 4104, if these
frames have less than 68 bytes (including FCS).
For example, it is valid to have an Ethernet frame of 64 bytes, even if it includes a 802.1q tag. However, when
the CPU switch forwards this packet through the
ETH2 port, it removes the 802.1q tag, but does not add any
padding byte. The Ethernet frame is output with only 60 bytes, which is invalid and dropped by most
equipment.
A workaround would be to modify the behaviour of your router to generate 802.1q frames with at least 68
bytes.
LAN and WAN with VLAN substitution
LAN and WAN interfaces with VLAN substitution is used to forward network traffic between the WAN and the
LAN interfaces of the Mediatrix 4104. It allows devices on the LAN side to communicate with the WAN side.
The ETH2 (LAN side) connector of the Mediatrix 4104 has an IP address and ETH1 (WAN side) connector
could also have one. You can configure the IP address of the ETH2 connector statically. The PC connected
to the Mediatrix 4104 could then use this address to contact the Mediatrix 4104.
For more information on how to set the ETH2 (LAN side) connector IP address of the Mediatrix 4104, refer to
“ETH2 Connector Static IP Address” on page 151 .
Switch Mechanism with LAN and WAN with VLAN Substitution
The following table describes the various behaviours of the switch mechanism.
Table 222: Seitch Mechanism Description
Behaviour Description
Switch of outbound packets The Mediatrix 4104 directly sends outbound packets either to the
WAN or to the PC, depending on the destination MAC address.
Switch of inbound packets from the
LAN If the destination MAC address is the Mediatrix 4104’s WAN MAC
address, the packet is processed locally; otherwise, it is
encapsulated into a VLAN 802.1q packet and sent to the WAN
interface.
Switch of inbound packets from the
WAN If the destination MAC address is the Mediatrix 4104’s WAN MAC
address, the packet is processed locally; otherwise, if it is a VLAN
encapsulated packet, the Mediatrix 4104 removes the
encapsulation and sends it to the LAN interface.