GPON and EPON have their own advantages. GPON is better than EPON in terms of performance indicators. However, EPON has the advantage of time and cost. GPON is catching up. Looking forward to the future broadband access market may not be a replacement, it should be complementary. For bandwidth, multi-service, high QoS and security requirements, and ATM technology as a backbone customer, GPON will be more suitable. For customers with low cost sensitivity, QoS and security requirements, EPON has become the dominant factor.
The PON (Passive Optical Network) is the main technology for implementing FTTH fiber-to-the-home. It provides point-to-multipoint fiber access. It consists of the OLT (optical line terminal) on the office side and the ONU (optical network unit) on the user side) and ODN (Optical Distribution Network). Generally, the downlink adopts the TDM broadcast mode and the uplink adopts the TDMA (Time Division Multiple Access) mode to form a point-to-multipoint tree topology. The biggest highlight of PON as optical access technology is “passive”. The ODN does not contain any active electronic devices and electronic power supplies. All of them are composed of passive components such as splitters, which have low management and operation costs.
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.
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.
1) an access network for telecom operations;
2) High bandwidth: line rate,downlink 2.488Gb/s, uplink 1.244Gb/s; high transmission efficiency, 94% (actual bandwidth up to 2.4G) behavior 93% (actual bandwidth up to 1.1G);
3) Full business support: The G.984.X standard strictly defines the support for carrier-class full service (voice, data and video);
4) Strong management ability: rich in functions, sufficient OAM domain is reserved in the frame structure, and the OMCI standard is formulated;
5) High service quality: multiple QoS levels, which can strictly guarantee the bandwidth and delay requirements of the service;
6) Low comprehensive cost: long transmission distance and high split ratio, effectively sharing OLT costs and reducing user access costs.
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 the future, IP carries all services, and Ethernet carries IP services.
1)The standards adopted by GPON and EPON are different. It can be said that GPON is more advanced, can transmit more bandwidth, and can bring more users than EPON. GPON originated from the early APON\BPON technology of optical fiber communication, and thus developed, the transmission code stream uses the ATM frame format. EPON’s E refers to the interconnected Ethernet, so EPON was originally required to be able to directly interface with the Internet, so the EPON code stream is the Ethernet frame format. Of course, in order to adapt to the transmission on the optical fiber, a frame format defined by EPON is encapsulated outside the frame of the Ethernet frame format.
2)The standard of EPON is IEEE 802.3ah. The basic principle of IEEE’s EPON standard is to standardize EPON in the 802.3 architecture as much as possible, and to extend the MAC protocol of standard Ethernet to a minimum.
3)The GPON standard is the ITU-TG.984 series of standards. The development of the GPON standard considers the support for traditional TDM services, and continues to adopt the 125ms fixed frame structure to maintain the 8K timing continuation. In order to support multiple protocols such as ATM, GPON defines a new package structure GEM:GPONEncapsulaTIonMethod. The data of ATM and other protocols can be mixed and encapsulated into frames.
4)In application, GPON has more bandwidth than EPON. Its service bearer is more efficient and its splitting capability is stronger. It can transmit more bandwidth services, achieve more user access, pay more attention to multi-service and QoS guarantee, but realize more complicated. This is because its cost is relatively high compared to EPON, but with the large-scale deployment of GPON technology, the cost difference between GPON and EPON is gradually narrowing.