Uploaded November 2025 | Updated September 2026, 1 week ago
In this talk we’ll discuss an open implementation of UET on XDP2. We’ll introduce the XDP2
model and APIs, and then we’ll dive into the design and source for building UET on XDP2.
XDP2 is a novel programming model for the high performance, programmable data plane. The
basic thesis of XDP2 is that it’s “write once, run anywhere, run well”. A user writes their data
plane program once in the language of their choosing. Compilers build their code for a variety of
targets, hardware or software, where for any given target the compilers build any optimized
image that with highest performance as allowed by the capabilities of the target.
The Ultra Ethernet Consortium (UEC) recently released the first specification for the Ultra
Ethernet Transport (UET). This is a modern transport protocol designed specifically for scale out
networking for AI/ML. The protocol needs to run at hardware speeds to meet the stringent
performance requirements of AI/ML workloads, but at same time the protocol is rather complex
so that a programmable implementation is desirable.
XDP2 is the perfect platform for UET. In our first implementation we have two lowest layers of
UET: the Packet Delivery sub-layer and Semantic sub-layer. We’ll demonstrate these in action
and sketch out the source code. We’ll discuss mapping the implementation in hardware for
highest performance
Tom Herbert: Tom Herbert is a visionary leader in networking, software development, and operating systems with 25+ years of industry experience. He has worked at Intel, Facebook, Google, Nvidia, and several startups leading development of SmartNICs, networking stacks, and operating systems for data centers at hyperscale. Tom is the inventor of several industry transforming technologies including XDP and a myriad of features in Linux networking. He holds five patents granted.
In this talk we’ll discuss an open implementation of UET on XDP2. We’ll introduce the XDP2
model and APIs, and then we’ll dive into the design and source for building UET on XDP2.
XDP2 is a novel programming model for the high performance, programmable data plane. The
basic thesis of XDP2 is that it’s “write once, run anywhere, run well”. A user writes their data
plane program once in the language of their choosing. Compilers build their code for a variety of
targets, hardware or software, where for any given target the compilers build any optimized
image that with highest performance as allowed by the capabilities of the target.
The Ultra Ethernet Consortium (UEC) recently released the first specification for the Ultra
Ethernet Transport (UET). This is a modern transport protocol designed specifically for scale out
networking for AI/ML. The protocol needs to run at hardware speeds to meet the stringent
performance requirements of AI/ML workloads, but at same time the protocol is rather complex
so that a programmable implementation is desirable.
XDP2 is the perfect platform for UET. In our first implementation we have two lowest layers of
UET: the Packet Delivery sub-layer and Semantic sub-layer. We’ll demonstrate these in action
and sketch out the source code. We’ll discuss mapping the implementation in hardware for
highest performance
Tom Herbert: Tom Herbert is a visionary leader in networking, software development, and operating systems with 25+ years of industry experience. He has worked at Intel, Facebook, Google, Nvidia, and several startups leading development of SmartNICs, networking stacks, and operating systems for data centers at hyperscale. Tom is the inventor of several industry transforming technologies including XDP and a myriad of features in Linux networking. He holds five patents granted.
