H35-210_V2.5 Exam Dumps : HCIA-Access V2.5 Exam

The EPON standard is one of many TDM-PON standards and has the basic characteristics of a TDM-PON network: a tree topology network is composed of OLT, ONU and ODN (Optical Distribution Network).

In the logical topology, the EPON protocol establishes a logical link for the OLT to each ONU, and the leading byte of the Ethernet data frame carries the logical link identity, that is, LLID (Logical Link Identity).

The downstream data stream from the OLT to the ONU is encapsulated as an Ethernet message, and the corresponding LLID is attached and sent in the tree PON network. The optical splitter in the ODN broadcasts the data stream to each branch, and all ONUs can receive the downlink Ethernet data frame, and selectively receive their own data according to the LLID.

In the upstream direction from the ONU to the OLT, each ONU uses the broadcast mode to share the upstream bandwidth.

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One ONU/ONT can contain multiple T-CONTs

tcont 1 generally carries OMCI channels

Uplink bandwidth is divided based on T-CONT, and different services use different T-CONTs

The GEM port is used as a service channel. A GEM port can carry one or more services in the flow