Albedo xGenius - Physical Layer Settings; Frame Settings

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User Guide
66
4.1.1. Physical Layer Settings
Before starting any frame generation test, the equipment must be connected to the
network and the electrical and optical physical layer must be correctly configured.
Ethernet technology has been designed to keep physical layer configuration to the
minimum. But there are at least two settings you may need to check before you get a
link from the DUT / SUT. These settings are the Connector (See section 2.2.1) and the
Auto-negotiation (See section 2.2.3). You will know that the port is prepared for traffic
generation and analysis when the 10G, 1000, 100 or 10 LED (See section 5.3) is
displayed in green colour.
4.1.2. Frame Settings
Most of the Ethernet frame fields are available for configuration in the test unit. Before
configuring these fields it is necessary to tell to the tester which frame structure is going
to be used for traffic generation. The Frame type is a port-wide setting. Once you
choose an specific framing for your traffic, all streams you define for the port carry the
same framing structure. The only currently available Frame type is DIX, The DEC, Intel,
Xerox (DIX) frame, structure also known as Ethernet II framing. DIX / Ethernet II
framing encode the payload type in the Type frame field. This is the most common
framing format found in real networks: For example, RFC 894 mandates a DIX /
Ethernet II frame structure with the Type field set to 0x0800 for IPv4 encapsulation.
Table 4.1: Ethernet Frame Settings
Setting Description
Encapsulation This field configures the way the data is encapsulated in
Ethernet frames for transmission in the current stream. The
allowed encapsulations are the following ones:
• None: A DIX or IEEE 802.3 frame carries the test data,
depending on the current value of the Frame type setting.
• VLAN: Transmitted frames are labelled with an IEEE
802.1Q frame tag. Settings related with configuration of
the VLAN tag are enabled when this option is selected.
• Q-in-Q: Transmitted frames carry two VLAN tags, one ser-
vice provider tag (S-VLAN) and a customer tag (C-VLAN).
The C-VLAN is identified by the normal IEEE 802.1Q Eth-
ertype and the S-VLAN carries one of the not-standard
Ethertypes.
• IEEE 802.1ad: Transmitted frames carry two VLAN tags. It
is similar to the Q-in-Q encapsulation but this option fol-
lows strictly the standard IEEE 802.1ad encapsulation for
Provider Bridges (PB). Specifically, the IEEE 802.1ad car-
ries the special 0x88a8 Ethertype within the S-VLAN.