The Network Times

BGP Route Advertisement The next step after configuring BGP peering using BGP Unnumbered with IPv6 link-local addresses is to advertise the host networks.

After enabling IPv6 on the Ethernet0 interface, we can configure BGP peering.

Chapter 6: BGP Unnumbered for IPv4 Introduction This chapter explains how an IPv6-only transport network can provide connectivity between IPv4 networks by using IPv6 link-local addresses as next-hop addresses for IPv4 routes.

The title of this section might seem a little overwhelming, but it reflects the focus of the chapter.

Step 3: Associate Ethernet0 to VLAN 10 After configuring VLAN 10 and bringing up interface Ethernet0, the next step is to make Ethernet0 an untagged member of VLAN 10.

Enable Interface Ethernet0 After creating VLAN 10, the next step is to enable interface Ethernet0.

Introduction In this chapter, we examine what happens under the hood when we configure a Layer-2 VLAN on a SONiC switch, enable two host-facing interfaces, and associate them with the previously created VLAN as untagged access ports.

The previous section described at a high level how the config_db.json file is loaded into the Redis CONFIG_DB database in the Database container.

Introduction Before a switch can forward data traffic, its ASIC must first be programmed with the device's port configuration.

Figure 3-1 illustrates a simplified SONiC container startup sequence.

ONIE-Based SONiC Installation Many switch vendors have added SONiC NOS support to at least part of their switch portfolio.

Introduction SONiC (Software for Open Networking in the Cloud) is a Linux-based open-source network operating system that was originally developed at Microsoft and is now maintained by a broader open-source community.

SONiC is a vendor-neutral, Linux-based network operating system (NOS) that uses a database-driven architecture.

Introduction This chapter explains how to create and deploy a simple SONiC-based Clos topology in WSL using Containerlab.

Introduction This chapter explains how to build a SONiC virtual test environment on a Windows computer.

Receive Network Processing Unit (Rx NPU) Figure 9-4 illustrates a simplified receive-side processing pipeline, starting from the moment a Packet Header Vector (PHV), constructed by the Rx IFG, is delivered to the Receive Network Processing Unit (Rx NPU).

Virtual Output Queue (VOQ) The Silicon One VOQ Architecture Instead of using dedicated deep interface buffers for packet queuing, Cisco Silicon One utilizes a Centralized Shared Memory architecture paired with a logical Virtual Output Queue (VOQ) mechanis…

Receive Interface Group (Rx IFG) Ingress Pre-Processing and Integrity The Receive Interface Group (Rx IFG) is the ingress pre-processing stage that handles the incoming Ethernet bitstream before the packet enters the Packet Processing Array (PPA) of the R…

Introduction The previous chapter introduced the Ultra Ethernet (UE) Transport Layer and its endpoint-centric congestion control mechanisms: Network Signaled Congestion Control (NSCC) and Receiver Credit-based Congestion Control (RCCC).

Introduction Receiver Credit-Based Congestion Control (RCCC) is a cornerstone of the Ultra Ethernet transport architecture, specifically designed to eliminate incast congestion.

Figure 6-14 depicts a demonstrative event where Rank 4 receives seven simultaneous flows (1).

Inflight Packet Adjustment Figure 6-12 depicts the ACK_CC header structure and fields.

Network-Signaled Congestion Control (NSCC) The Network-Signaled Congestion Control (NSCC) algorithm operates on the principle that the network fabric itself is the best source of truth regarding congestion.

Ultra Ethernet Transport (UET) uses a vendor-neutral, sender-specific congestion window–based congestion control mechanism together with flow-based, adjustable entropy-value (EV) load balancing to manage incast, outcast, local, link, and network congestion

Calculating Base RTT [Edit: January 7 2026, RTT role in CWND adjustment process] As described in the previous section, the Bandwidth-Delay Product (BDP) is a baseline value used when setting the maximum size (MaxWnd) of the Congestion Window (CWND).