XGS-PON is the next-generation evolution of GPON; therefore, the XGS-PON scenarios are similar with the GPON scenarios. XGS-PON application scenarios can be divided into three parts: the cell station users, the business users and the residential users. The cell station user scenarios is FTTCell. The type of the ONUs used in the FTTCell scenario is called Cellular Backhaul Unit (CBU), which supports base station backhaul. CBU needs to support IEEE1588 and Synchronous Ethernet. The commercial user scenarios include FTTB and FTTO. The types of the ONUs used in the commercial user scenarios are MTU and SBU, which support commercial data transfer, E1 services, commercial video conferencing, and commercial voice conferencing. The residential user scenarios inculde FTTH, FTTdp, FTTB and FTTC. The types of the ONUs used in the residential user scenarios are SFU and LAN based MDU as well as the DSL and G.fast based MDU, which provide high-speed Internet services, voice services and video services.
XGS-PON Application Scenarios (Excerpted from G.9807)
Compatibility between XG-PON and XGS-PON
The OLT XGS-PON port supports the coexistence of XG-PON ONUs and XGS-PONONUs via TDMA in upstream and downstream directions, and supports receiving the data burst at 9.953Gb/s and 2.488Gb/s, thereby suiting diversified scenarios. The same XGS-PON port supports accessing the business users who demand for symmetric bandwidth as well as the home users who demand for asymmetric bandwidth, which meets the requirements of different users and reduces the investment of the carriers on terminal devices.
Coexistence between XGS-PON and GPON through WDM1r
GPON and XGS-PON can coexist through WDM (Wavelength-Division Multiplexing). The XGS-PON wavelengths and GPON wavelengths in the upstream and downstream directions are completely isolated from each other. The four wavelengths can coexist inthe same ODN without interfering with each other. WDM1r is a wavelength combiner, which combines the GPON downstream wavelength from the GPON interface and the XGS-PON downstream wavelength from the XGS-PON interface into the same fiber for transmission, and separates the GPON upstream wavelength and XGS-PON upstream wavelength from the same fiber to the GPON and XGS-PON interface respectively. This scenario supports the coexistence of XGS-PON ONUs and XG-PON ONUs under the same XGS-PON interface.
Conclusions
Based on ITU-T G.987 and ITU-T G.989 series PON standards, XGS-PON expands the capabilities, providing symmetric large-bandwidth services, and supporting the coexistence of GPON and RF video in the same ODN as well as the coexistence of XGS-PON ONUs and the XG-PON ONUs. With the coming of the Gigabit era, XGS-PON has been gradually mature and commercialized. IDXLINK takes the lead in XGS-PON productization and commercialization. XG(S)-PON Combo OLT XGW08C and 2U XG(S) PON OLT XGW16C-X2 Series launched by IDXLINK is an optimal choice for the operators to upgrade their networks.
