Enhancing Long-Haul Network Resiliency with OcNOS®

23rd May 2022
Telecommunication networks are increasingly stretched to deliver greater and greater capacity as enterprises and subscribers begin using 5G-enabled devices. In anticipation of 5G networks, optical engineers have developed innovative ways to increase the capacity of existing physical infrastructure.
Technological advancements have significantly increased the data that can be packed into a single optical channel for efficient transmission over long and short distances. For example, coherent optics, modulate both amplitude and phase for transmission across two polarizations to create disaggregate OTN networks, as discussed in “Disaggregated OcNOS®-OTN Transforms Network Capacity.”
Figure 1 Coherent Optical Transponder in DWDM Systems ipinfusion.com Figure 1: Coherent Optical Transponder in DWDM Systems
Legacy Dense Wavelength Division Multiplexing (DWDM) technology served its original purpose, delivering greater amounts of data from point A to B. However, network resilience is costly to achieve for long-haul carriers because of the additional equipment they need to purchase, deploy, and operate, manually-intensive network reconfiguration.
IP Infusion’s vendor-agnostic OcNOS software addresses this challenge with its latest Optical Transport Network (OTN) Solution update. The update allows operators to substantially improve resilience over longer distances without the investment in additional equipment and labor. So, what is resilience, and how does a disaggregated network make it better?

The Long-Haul Network Resilience Conundrum

A resilient network is fault-tolerant — aside from a natural disaster, it is always expected to achieve its target service levels. But a lot can happen during optical transmission, making resiliency especially important for long-haul and metro (busy networks) data transport.
The extended distances and extremely high data rates increase the likelihood of link failure. While link failures are a common and expected occurrence, the industry has set a gold standard of 50ms for resolution. For long-haul DWDM networks it becomes capital and operating expenses (CapEx and OpEx) intensive because of the amount of hardware and reconfiguration required to restore the link within 50 ms. The limiting factor is the time to detection — faster detection times on DWDM networks require more vendor-specific hardware.
To meet the growing network bandwidth requirements, IP Infusion’s OcNOS® Optical Transport Network (OcNOS-OTN) integrate coherent optics such as 400G ZR & Open ZR+ on the Cassini Packet-Optical platform, increasing the load-carrying capacity. The ZR/ZR+/openZR optics afford ISPs and data centers higher carrying capacities of 200-400G in the smallest pluggable form factor. With the proper configuration, providers can achieve up to 800G+ per channel and longer carrying distances at a lower cost than legacy DWDM technology.
Figure 2 Optimization of pluggable small form factor ZR optics ipinfusion.com Figure 2: Optimization of pluggable small form factor ZR optics

How OcNOS Delivers Resiliency

Simply put, resiliency is built into IP Infusion’s innovative OcNOS disaggregated network solution, the industry’s trusted carrier-grade feature-rich software platform for white box solutions.
OcNOS detects, verifies, and isolates connectivity failures using Connectivity Fault Management (CFM) in compliance with the MEF 17, IEEE 802.1ag 2007, and ITU-T Y.1731 Service OAM standards.
CFM provides the Layer 2 fault isolation through continuity check protocols. OcNOS supports CFM across multiple vendors’ equipment.
Figure 3 OcNOS with CFM reduces fault detection times and enhances network resiliency ipinfusion.com Figure 3: OcNOS with CFM reduces fault detection times and enhances network resiliency
The OcNOS update allows continuity check messages (CCMs), or the lack thereof, to be detected by maintenance endpoints (MEPs) across carriers with shared facilities. Faults may be detected on multiple transmission signals and applied to the maintenance process as well. In addition, other CFM protocol data units (PDUs), including loopback and linktrace, are included in the shared operator capabilities to enhance the entire failure repair process. As such, OcNOS with CFM over xConnect decreases connectivity failure repair times and enhances network resiliency by using these dynamic CFM capabilities (see Figure 3).
Network administrators are alerted to link failures when CCMs are not received at the maintenance endpoints (MEPs). The MEPs exist at the edge of the domain, and detect link failures once valid CCMs are not received. When the CFM over xConnect feature detects a fault, traffic will be redirected to a backup path from the failed primary path
These factors facilitate L2 resiliency in the network as link-failure detection times are drastically reduced, facilitating faster traffic switchover to a backup link.
IP Infusion’s CFM over xConnect solution is designed to improve the delivery of voice, IPTV, internet, L2 and L3 VPN, and operations, administration, and maintenance (OAM) services in the long-haul. It has been optimized for vendor-agnostic fault detection in long-haul transmission, while offering the tunability and configurability operators expect.

xConnect Resiliency Is Carrying Long-Haul Providers Into the Future

By implementing this Cassini-based OcNOS-OTN solution, network operators will achieve a reduction in both OpEx and CapEx. Because the Cassini packet-optical platform is vendor agnostic and offers configuration flexibility, savings are experienced through a reduction in hardware and labor costs for carriers of all types. OcNOS-OTN provides the best way for long-haul carriers to keep up with demand and meet consumers’ price points while remaining in the black.
In addition, the coherent optics devices can be used in an IPoDWDM fashion to help further expand available bandwidth and extend reach, making the solution less expensive. OcNOS-OTN offers long-haul operators the opportunity to deliver resilience with less interruption at a low cost, allowing them to scale up operations while meeting the 50 ms failover requirement.
For more information about leveraging MEF’s service OAM framework with xConnect to increase resiliency, download the IP Infusion OTN Long Haul xConnect Resiliency Application Note.
To learn more about how IP Infusion can enhance your long-haul or metro network resiliency, please visit ipinfusion.com.