What is EPON ?
EPON is an IEEE standard. EPON uses a point-to-multipoint architecture and passive optical fiber transmission to provide multiple services over Ethernet. At present, IP/Ethernet applications account for more than 95% of the entire LAN communication. EPON is the most effective communication method for connecting end users of the access network by using the above-mentioned economical and efficient structure. The emergence of 10Gbps Ethernet backbone and metro ring will also make EPON the best last mile solution in the future all-optical network.
In an EPON, optical signals can be accurately transmitted to end users without any complicated protocols, and data from end users can be centrally transmitted to the central network. At the physical layer, EPON uses the 1000BASE Ethernet PHY, and at the same time, on the PON transmission mechanism, the newly added MAC control commands are used to control and optimize the bursty data between each optical network unit (ONU) and the optical line terminal (OLT). Communication and real-time TDM communication. In the second layer of the protocol, EPON adopts mature full-duplex Ethernet technology and uses TDM. Since the ONU sends datagrams in its own time slot, there is no collision and no CDMA/CD is required. Make the most of your bandwidth. In addition, EPON provides QoS similar to APON/GPON by implementing 802.1p in the MAC layer.
What is GPON ?
GPON, FSAN and ITU have standardized it. Its technical feature is to use ITU-T-defined GFP (General framing procedure) to encapsulate and map various services such as Ethernet, TDM and ATM at the second layer, which can provide 1.25Gbps and 2.5Gbps downlink rate, and 155M, 622M, 1.25Gbps, 2.5Gbps several uplink rates, and has a strong OAM function. If you don't consider EPON, you will see that it will increase to 10Gbps (10G Ethernet is mature). Currently, GPON has advantages in high-speed and multi-service support, but the complexity and cost of technology are currently higher than EPON.
PON system is undoubtedly one of the best, EPON and GPON, both technologies have their own advantages, whether it is EPON technology or GPON technology, its application is largely determined by the rapid reduction of fiber access costs and business needs, and the price is the most core factor.
PON OLT Network Application
EPON vs. GPON
EPON is compatible with the current Ethernet technology. It is the continuation of the 802.3 protocol on the optical access network. It fully inherits the advantages of low Ethernet price, flexible protocol and mature technology. It has a wide market and good compatibility. GPON is positioned in the telecom industry for multi-service, QoS-guaranteed full-service access needs, and strives to find an optimal, full-service, and most efficient solution, and proposes to "completely open all protocols." Rethinking."
The technical features of EPON are as follows:
1) Ethernet is the best carrier for carrying IP services;
2) Simple maintenance, easy to expand, easy to upgrade;
3) EPON equipment is mature and available. EPON has already laid millions of lines in Asia. The third generation of commercial chips has been launched. The prices of related optical modules and chips have dropped significantly, reaching the scale of commercial scale and meeting the requirements of recent broadband services. ;
4) The EPON protocol is simple and low in implementation cost, and the equipment cost is low. The most suitable technology is needed in the metro access network, not the best technology;
5) More suitable for domestic, the metropolitan area network does not have ATM or BPON equipment package;
6) More suitable for the future, IP carries all services, and Ethernet carries IP services.
The technical features of GPON are as follows:
1) Access network for telecom operations;
2) High bandwidth: line rate, downlink 2.488Gb/s, uplink 1.244Gb/s; 3) high transmission efficiency: 94% (actual bandwidth up to 2.4G) behavior 93% (actual bandwidth up to 1.1G);
4) Full service support: The G.984.X standard strictly defines the support for carrier-class full service (voice, data and video);
5) Strong management ability: rich in functions, sufficient OAM domain is reserved in the frame structure, and the OMCI standard is formulated;
6) High service quality: multiple QoS levels, which can strictly guarantee the bandwidth and delay requirements of the service;
7) Low comprehensive cost: long transmission distance and high split ratio, effectively sharing OLT costs and reducing user access costs.
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