University:
California State University, East Bay
Course:
CS 3590 | Data Communications and Networking
Academic year:

2023
Views:

419

Pages:

1
Author:

Jithin J I

PASSIVE OPTICAL NETWORKS Passive optical networks (PONs) are favorable access networks due to high performance, low cost, and fulfilling user bandwidth demands. Time division multiplexed PON (TDM-PON) shares bandwidth and hardware between users, reducing cost but compromising bandwidth. Wavelength division multiplexed PON (WDM-PON) uses dedicated wavelengths for each user, increasing bandwidth. It is considered a next-generation PON. Greenfield vs Brownfield Deployment Greenfield: Directly replacing copper networks with WDM-PON Brownfield: Migrating from existing TDM-PON to WDM-PON. Requires coexistence of both networks on same infrastructure. TDM-PON to WDM-PON Migration  TDM-PON: Downstream amplitude modulation  WDM-PON: Downstream minimum shift keying (MSK) modulation  WDM wavelengths separated from TDM using filter  Upstream WDM signal remodulated onto downstream wavelength Simulation Setup  4 users on 10Gbps TDM-PON, 4 users on 40Gbps WDM-PON  TDM: 2.5Gbps amplitude modulation  WDM: 10Gbps MSK modulation  30km fiber transmission Results  Even after upgrade, TDM users get error-free signals with ~3dB power penalty  Crosstalk from upgrade causes <50% power loss  Performance of legacy TDM network not affected much by WDM upgrade  MSK outperforms DPSK in WDM-PON based on previous works Conclusion  Migration from TDM-PON to WDM-PON demonstrated with minimal impact  Allows increased bandwidth and convergence while reusing infrastructure