How many TCP segments is a reasonable number for a TLS Client Hello?

Depending on your network set up, for connecting to bgp.tools until maybe a couple of hours ago the (non reasonable, but real) answer may have been up to 22!

It turns out on IPv4 bgp.tools has been advertising the wrong TCP window scale for quite some time and it's a true testament to TCP's flexibility that any of this was working in the first place.

Regardless, connection setups on bgp.tools should now work a little better on IPv4 now that your machine wont have to send 21 extra packets

inet_aton wins again

Here I was waiting for output on a tcpdump -ni any host 3306... that should have been port 3306, but of course in the world of inet_aton "3306" is a valid IP address of 0.0.12.234!

Thanks inet_aton!

Some other fun things I spotted in the Cogent Q4 2025 investor presentation:

A) Cogent is now averaging at 800 tbit/s of traffic

B) While their office broadband biz is 4%~ of their total traffic, it's 43% of their $ revenue! Not bad!

C) For their off-net IP offering (aka, they use another provider to do the last mile) over half of the cost to the customer is to the last mile loop provider!

Full thing here: https://www.cogentco.com/files/docs/about_cogent/investor_relations/presentation/Cogent_IR_Presentation_4Q25.pdf

Hah, Cogent CEO seems to recognize that having the ability for customers to make RPKI ROA's on their space (aka, signing a ARIN agreement) made its IPv4 rentable there's a lot more appealing to customers!

It's a outrage that Firefox only has these two adorable error icons for the mascot so far: https://github.com/mozilla-firefox/firefox/tree/4cbe9648c5d4c1cf600b7a8c3589e4589541ded5/toolkit/themes/shared/illustrations

🦎

As a emoji in work presentations connoisseur, it pains me that the best ✨ emoji implementation was the original Twemoji, before in 2017 it went from purple to just boring yellow sparkles.

( I also hate that sparkles has been used to signal AI features :( )

Also, always embed actual PNGs of your emoji into your presentations, to avoid a surprise jankmoji (normally the windows ones) when your stuff gets loaded on to the event presentation laptop

yeah sci-hub bird, I was surprised too

You know, somehow, a IDE update on April 1st is really unappealing, I'll pass

Sir, another "Customers should enact their disaster recovery plans" has hit the AWS status page

Blocked by the pope :(

Damn they really did save that day light last weekend didn't they

"Move wells cathedral to Keynsham so Keynsham gets city status" https://petition.parliament.uk/petitions/764430

Airport adverts are a genre on their own, like how many bong rips was required to come up with all of the HSBC ones in LHR?

"aaaaaaaaaaaaaaaaaaaaaaaaaa"

Netbox labs going for that Jurassic Park nostalgia with their "NetBox Visual Explorer"

https://netboxlabs.com/blog/see-your-infrastructure-introducing-netbox-visual-explorer/

Less than 1GW of fossil fuels on the GB grid klaxon!

I can only conclude that PeeringDB is increasingly vibe coded (in the fullest meaning) because they keep releasing busted code that clearly has not been tested. Today they email me and a lot of other networks with a non sensical email that tells me to do something that does... nothing.

https://github.com/peeringdb/peeringdb/issues/1936

I can sometimes understand the desire to use AI tools, but seemingly none of this stuff is actually going through even basic testing in a staging environment, so frustrating for a service that absorbs quite a lot of sponsor money from orgs

Making an account on something today when I came across a novel to me password restriction

why why why the does Thunderbird let you sort by email subject, I have never wanted to do this and I always do it if I "miss" trying to open the newest email, and when you have a 100k+ inbox this little maneuver's is gonna cost you 51 years of CPU time

[deepest possible sigh]

( and yes, it is a real job listing )

✅ Muted all RIPE Charging Scheme members-discuss emails

There is basically nothing new to discuss and everyone is just going in the same conversation loop, all at expense of filling my inbox with crap

I would kill for an induction hob that has a magnetic stir bar system, how has cooking not stolen this trick from the chemistry world

New post!

How far can you go with IX Route Servers only?

IX Route Servers are internet peering on easy mode but how effective is it really? I couldn't find any studies on this so I decided to look myself using the bgp.tools IX collector network!

https://blog.benjojo.co.uk/post/how-far-can-you-get-with-ix-route-servers

EMF-IX Returns

EMF-IX, the #emfcamp / #emfcamp2026 internet exchange will be returning for EMF 2026.

Complete with our best switch yet (the "no cost spared" Juniper LAN) this will be the best EMF-IX yet, run a personal network or similar? Reserve your (in person) port today: https://emf-ix.benjojo.co.uk/

This year the EMF Camp network itself will be peering on the exchange as well!

✅ EMF Ticket

#emfcamp #emfcamp2026

A supplier security-questionnaire.xlsx, but you lose the bid by simply opening it, because who opens random microsoft office documents over email in this day and age?

NetLdn #70 – 12/03/2026:

Join us for two talks this Thursday!

https://netldn.uk/2026/03/03/netldn-70-12-03-2026/

I was today years old when I found out that the Nürburgring (the world famous race track) is no where near Nuremberg.

I wonder how many people have incorrectly traveled to Nuremberg with the expectation of using/visiting the track

Yeah fuck it just turn it off and on again

The devastating moment when you go back to your bedroom to get something and your bed sheets still retain a bit of the warmth from the morning

Need to get around to writing a photo library for my (assume oddly specific ) needs like:

• SQL like query over EXIF data
• Per photo statute of limitations tracker
• Something that doesn't consume all of your local storage
• Doesn't require a jenga tower of dependencies like immitch

I love how if you look at the total unique prefixes in the BGP DFZ over 3 months you see these small spikes (less than 30 min) of like 4000~ prefixes, implying that someone accidentally exported their more specifics and obliterated a subset of their transits/peering sessions, causing the roll back.

But the table grows regardless

Swampy ambience

The kind of photo where you inadvertently take a selfie via another creatures eye

love birbs

deer having a epiphany/deep thought

Ah yes, the [checks AMD reference manual] "P2D Swiss Cheese Descriptor" CPU MSR, of course

You think web page size bloat is bad on some things? oh boy.

Good afternoon to everyone, except bumn.go.id (an Indonesian government website) for having a (at least) 3GB web page because of embedded MP4's with uncompressed audio and video seeming straight from the camera...

This must cost so much for them, like a single page load could cost at least $0.15 in cloud egress fees alone

Well the Andrew Mountbatten-Windsor episode of "24 hours in police custody" will be interesting

This is a sad way for something like Packet.net to end, First sold to Equinix metal and then shutdown, then it's customer list (silently?) sold to some other company as a marketing channel.

I don’t SPRINT. I do not SCRUM. I do not TIMEBOX. I do not give my tasks STORY POINTS. I choose my work based on WHAT NEEDS TO HAPPEN. And if your task gets in the way of my investigations? It DOES NOT HAPPEN.

@benjojo image + caption combo (shame the Bernese Mountain Dogs "appreciating gardens" was removed)

@benjojo While trying to find my favourite odd one I found the cow one. Haven't found to which page it originally belongs to.

https://en.wikipedia.org/wiki/Wikipedia:Unusual_articles

@benjojo partial to the classic https://en.wikipedia.org/wiki/Static_electricity#/media/File:Cat_demonstrating_static_cling_with_styrofoam_peanuts.jpg

What is your favourite Wikipedia image, I'll start with the

" Chaos magic ritual involving videoconferencing .JPG "

https://commons.wikimedia.org/wiki/File:Chaos_magic_ritual_involving_videoconferencing.JPG

Do you find yourself in the position where you just bought a piece of server kit (new or used) and you do not know what the IPMI password is, and you don't have a OS/screen to reset it, or it's set to some static IP that you don't know?

Please enjoy this small (70MB) image you can put on a USB stick and blindly boot the machine into, assuming the USB boots, it will set the IPMI to a known value, and set the network back to "normal" values (no VLAN and DHCP)

Enjoy! (and report back if you find it worked on things not already confirmed in the readme)

https://github.com/benjojo/headless-ipmi-reset

Successfully lived long enough to finally see (meaningful) IRCv3 support land on libera chat

fwiw, it seems like the greynoise assertion that the T1s are dropping the telnet port is bollocks

I present: The HSM alignment chart