- FiberMall
FiberMall
Answered on 2:00 am
Yes, Arista 40G QSFP can be used in Arista 100G QSFP switch ports, but with some limitations and considerations. Here are some points to note:
Arista 40G QSFP are compatible with Arista 100G QSFP switch ports that support 40G/100G dual-speed mode. This means that the switch port can operate at either 40G or 100G depending on the transceiver type and configuration. Not all Arista 100G QSFP switch ports have this feature, so you need to check the switch model and documentation before using a 40G QSFP in a 100G port. The following switches support 40G/100G dual speed mode:
- Arista 7060X4 Series
- Arista 7280R3 Series
- Arista 7500R3 Series
- Arista 7800R3 Series
Arista 40G QSFP can only interoperate with other Arista 40G QSFP or compatible devices that use the same standard and protocol. For example, a QSFP-40G-SR4-A transceiver can only interoperate with another QSFP-40G-SR4-A or a device that supports 40GBASE-SR4. You cannot use a QSFP-40G-SR4-A to connect to a device that supports a different standard, such as 40GBASE-LR4 or 100GBASE-CWDM4.
Arista 40G QSFPs can be used in breakout mode to connect to four 10G SFP+ ports using a special cable. This allows you to use a single 100G QSFP switch port to connect to four devices that only have 10G SFP+ ports. However, this also reduces the bandwidth of the switch port from 100G to 40G.
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