Every access point datasheet carries a PHY rate: 5.4 Gbit/s, 11 Gbit/s, 46 Gbit/s for Wi-Fi 7. The number is the modulation table. What a client gets in a meeting room wi…
Alexander Zemskov
4 min read
The datasheet of a firewall or a load balancer states "TLS throughput". The footnote, when there is one, says TLS 1.2, RSA 2048, one cipher, 64 KB objects, inspection off…
Alexander Zemskov
4 min read
A data centre fabric is accepted in 2 steps. Step 1: the integrator shows that two hosts on different leaves can ping. Step 2 happens 6 months later, when a hypervisor mi…
Alexander Zemskov
4 min read
An AI cluster spends a share of its time waiting for the network. A single dropped RoCE packet triggers a go-back-N retransmission, the collective stalls, and 256 GPUs id…
Alexander Zemskov
4 min read
The IPsec line on a firewall datasheet is measured with one tunnel, large packets and the fastest cipher the chip supports. Your site-to-site estate is 800 tunnels, a mix…
Alexander Zemskov
4 min read
MPLS is where the control plane and the forwarding plane most often disagree. The LSP is up in the CLI and the packets still go somewhere else. We test the two together: …
Alexander Zemskov
4 min read
An IGP has one job: tell every router where every link is, fast. The protocol is 30 years old and the implementations still differ by a factor of 10 in how quickly they d…
Alexander Zemskov
4 min read
A router datasheet says "BGP: 4M routes, 1,000 peers". The number is true in the sense that the table fits in memory. It says nothing about how long the box takes to inst…
Alexander Zemskov
4 min read
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