Back from AusNOG. It's now clear that allocations of new IPv4 addresses will cease in 2010, so a lot of the conference was about NAT and IPv6.

IPv6 is too late. Although no one said so, we've basically been let down by vendors unwilling to ship product for which there is "no demand", governments too afraid of regulation to insist, and an industry too focussed on the present to lobby government to make them insist. It hasn't helped the industry/government interface that government's brain-dead content filtering plans have sucked the air from any other industry/government discussions.

So it's going to be "carrier-class network address translation". That is, your ISP will run NAT (and if you are the average customer, you will run NAT on your ADSL router too).

You are now going to need the ISP's support to run some applications. The ISP has a profitable telephony business? Then they could re-route the H.323 and SIP telephony control protocols to their telephony core. All in the name of clearer calls and increased reliability, with pricing to match. Nothing you can do about it, since their NAT doesn't support H.323 and SIP to anywhere else.

As for running your own web/mail/whatever server; that's not going to happen anymore.

That's right, it's the return of the Walled Garden. You can only do what the carrier wants, and they're going to charge as much as they can for that service. Gone will be the days of the Internet as a low rent transport.

Also, an ISP with all of their customers hanging off the One True NAT is going to be cautious about configuring and upgrading that NAT box. You want support for SNMP, sorry, too technically risky (all those ASN.1 complexity attacks) and not enough demand. You want support for the just-released protocol TuxRacerNetworkEdition? Nah, we're not going to potentially annoy our 250,000 users to satisfy 25 users.

As a hobbyist consumer, you want IPv6. Because that's the only way you'll be able to run your own services. Because that's the only way you'll be able to access the Internet, not just the interweb.

If you are a gamer, you really want IPv6. God knows what the latency will be to and from that NAT box.

Ask your ISP. Ask in your router manufacturer's forums for IPv6 support. And ask for that support in the shipped hardware you already own. They've had enough notice of the end of new IPv4 addresses, so it can only be called a bug that your router doesn't already support IPv6.

"Generation Tech" in CIO Magazine. Interestingly Sue used LinkedIn to collect people's views for the article. First and last half-decent use for LinkedIn I have seen.

I'll reserve my rant on the bizaare business title which is "CIO" for some other time.

One day I will go to a conference as an attendee. I will not organise. I will not present. I will not schmooze customers. I will not solve deep network design issues in the foyer. I will not attend hallway meetings. I will not do secret deals to improve the stability of the net. I will not be up late sweeping the floor rather than partying at the nightclub. I will receive schwag rather than disburse it. I will attend presentations, not be making that demo work from behind the curtain.

Putting that dream on hold, it looks like I'd be giving an end-to-end network performance workshop at QUESTnet 2008. Followed by a long presentation on how to make BGP, firewalls and OSPF all work happily together so that they all dynamically route and fail over in a reasonable way.

The workshop should be good value, we'll hammer routers, firewalls and computers until their pips squeak. Last time I did something like this one of the PCs caught fire and we broke a router so bad its FPGAs had to be reloaded from its JTAG bus.

If you are a vendor and think your equipment is better than those then drop me a line -- workshops are a good opportunity for non-dominant vendors to get their gear looked over by decision-influencing people. If you have a solid firewall that actually does 1Gbps or a switch with fair packet loss then this would be a good opportunity to spread the word.

Since this blog is named "Postcards from Semaphore" and I notice The Australian is critical of the lack of paid lifesavers at the beach I should give people some background.

Semaphore Beach is about 2Km long, curving in a large S. The Surf Lifesaving Club is to the south, the Semaphore Jetty is to the north. The beach continues on to the south and north in the same fashion, merely changing name to Tennyson and Largs. The shape of the beach means that one end of the beach is not visible from the other end.

Inland there are sand dunes and beyond those are plentiful grassed areas where people have BBQs, play games and ride bikes. There are large wonderful playgrounds for the kids, adjacent to kiosks for the adults. Inland again are huge car parks, with occassional public conveniences. The boundary of the beach is marked by The Esplanade.

On hot evenings in Adelaide many thousands of people come to Semaphore Beach, as the Beach is the nearest surf for about a third of Adelaide's population. The Esplanade becomes congested with traffic. Locals walk or pushbike to the supermarket on the main street as there is no hope of a car park. The Jetty, being at the end of the main street, is very popular. A walk out to the end of the Jetty and back is popular with old and new lovers. Many people wade through the water next to the Jetty to cool their legs, without any thought of actually swimming.

Despite the high usage, Semaphore has the least state government investment of the metropolitan beaches. This inattention is partly to do with the lack of available land for further housing development, as nothing attracts this state goverment like a billion dollar housing development such those at as West Beach and Glenelg. On an operational level, treating the Beach as vacant is useful for the government as it allows it to mine the Beach for sand to use on the other beaches (Adelaide's beaches lost their sand due to seaweed dying from pollution runoff, the increased northerly current dropping the eroded sand at Semaphore).

The beach itself is usually shallow, which accounts for the long length of the jetty (which is only one-third of its original length, in the days when sailing ships docked there). There are a number, usually two, large sandbars only some of which are exposed at low tide.

Somewhere between 20m and 50m out to sea the sandbars end and the deep water suddenly starts within a single step.

There are a number of deep channels through the sandbars. These are created by the currents rushing through to fill or empty the pools of water between the exposed sandbars. A strong northerly current tends to push those unaware along the beach and into the channels.

At the south of the beach is a groine. This attractive nuisance is a island created from geotextile bags. By design, high tide washes across the top of the island. It was placed there by the state government to prevent the current from carrying the sand away from under some housing built too close to the beach in a 1980s housing development.

Roughly one person dies on the beach each year. About half are drownings, the others being drug overdoses and nasty people choosing the the wintertime solitude of the sanddunes to do their evil work and the like. The drownings are usually of poor swimmers, caught by unexpectedly deep waters.

One occured on the groine, the summer it was installed. A non-swimmer girl was caught out by the high tide leaving her nowhere to go. The state government foolishly then added signs rather than also building a refuge which would give others time to save those in danger.

The most recent occurred near the Jetty. A non-swimmer was walking along a submerged sandbar and either walked off the edge or walked into a channel. A little dog paddle along with the current is all that is needed for self-rescue, but sadly the person must have flailed about with no purpose.

Today's article in The Australian complains that there are no paid lifesavers at the Beach. I'm not sure they would have helped and this sounds like a complaint from someone unfamiliar with our Beach. The Surf Lifesaving Club can't be seen from the base of the Jetty.

I've no idea how or why the SLSC moved from alongside the Jetty to way down south. Photos from the 1930s show it alongside the Jetty. Maybe it is time to move it back, although that just reverses the problem.

The Club itself seems an odd beast from the outside. At the recent local council elections it supported the a particular candidate for Mayor of Port Adelaide. I've no idea why the Semaphore SLSC sought a role in partisan local politics. It seemed at the time to be highly inappropiate. It certainly limits support for the Club, both in participation and in donations.

In summary, Semaphore Beach is safer than many beaches. It is shallow, the waves are broken far out to sea by the sandbars, there are no huge rips. The risk is simply that of the suddenness of deep water if you move about.

I have small kids. I drop my bags in a spot away from a channel. Then I keep fetching the kids back to the spot marked by the bags. I don't pick up the bags and follow the kids, as they will inevitably be pushed northwards by the current and end up in the channel just south of the Jetty. The kids get about 10m of scope, which isn't enough to fall into the deep water off the ends of the sandbars. I usually go into the water with the kids.

I wouldn't play on the groine. If one of those bags splits or shifts and grabs a limb then nothing will save you. Swimming through the current on the inside of the groine is a bitch. Swimming around the outside is no better, as the surge tends to push you inwards onto the groine whilst the current is simultaneously pushing you outwards, so it takes a lot of work to keep on track.

Since it has been 40C and no one in their right mind is outdoors, I chose this week to finally build a bike shed. Bunnings had a ABSCO galvanised shed 1.51m x 0.78m for A$199. A bike will just fit into this space. I used two wall hangers for bikes mounted at opposing ends of the shed to squeeze in two bikes. The wall hangers need something other than the shed wall to hang off, I just used some wood which I ran floor to roof and fixed with long TEKS screws through the wood and into the shed frame. There is a fair bit of room at head height down the long rear wall of the shed, so I put a high shelf in there to hold bottles, helmets and the rest of the clutter.

The shed did not come with a mounting kit but showed every indication of wanting to visit the neighbours during the next gale. I had some old metal strapping which I riveted to the frame of each wall, bent the strapping at a right angle, drilled a hole, and used that hole to connect with the top of a Dynabolt drilled into the concrete driveway.

Two bikes was a tad ambitious: it's fiddly getting the bikes in and out. If you need a shed for two bikes paying the extra A$100 for a 1.5m x 1.5m shed would be a better choice for others. We've got six people living on a small block, so every sq.m counts and we'll live with the fiddliness. You would certainly want the 1.5 x 1.5 for a motor scooter.

Not sure I'd buy a ABSCO shed again. The instructions are nothing more than technical drawings, and despite my best efforts there was an amount of re-work during the final assembly when the meaning of previously ambiguous line drawings became apparent. The quality of the shed itself is good -- everything fits tightly, keeping the weather out. But the materials are thin and flimsy -- but this is the smallest shed in the cheapest range. Construction took about six hours across three days, but I'm sure other people on colder days could do it in half the time.

The door lock is a joke, since the hasp mounts with screws. The lock needs some rivets and two 20mm Security TEKS screws (you just know that when you get to the hardware store they are only going to be available in blister packs of 50). I simply decided not to bother with it, but to chain the bikes inside the shed. To give the bike locks something to run through I riveted two chest handles onto the shed wall. I reinforced the shed wall with some galv plate so a decent tug won't deform the wall and allow the rivets to pull through.

On holidays, until February. Wonderful. None of this "recharging the batteries" nonsense -- "It's my leave and I'll party if I want to".

Of course, back on Planet Earth, I'm minding a six year old for all of those weeks. So partying is as unreaslistic as any notion of recharging.

In the interests of Worldwide Parental Sanity these notes will occassionally mention good places for the under-10s, if only so I've got somewhere to check back to when mid-holiday child-accelerated dementia strikes.

  • The beach at Semaphore. Noonies Kiosk to the south is much nicer than the kiosk by the Semaphore Jetty. Like the Jetty it has a very fine playground. Unlike the Jetty it has no paid attractions. Greek Festival 12-13 Jan.

  • Port Adelaide Railway Museum. No pretentions here, the kids can climb on the old steam trains. There's a small train circling the buildings. Allow all day.

  • Adelaide Zoo. It's expensive, so become a member. It's astonishing how much more fun it is when you can just wander in. Allow all day.

  • Port Adelaide Maritime Museum. The attractions here don't change very often, so if you went last holidays you won't get much more from going these holidays. But the permanent attractions are very, very good: the kids can go on a real ketch, check out ship accomodations from the establishment of Adelaide until the 1950s (when economy class flights replaced steerage). Allow half a day.

  • Adelaide Acquatic Centre. Lots of pools for the kids, free waterslide. Unfortunately a lot of the areas are often roped off in the holidays for VacSwim. Allow all day.

  • Victor Harbour. The main attraction is the 5C drop in temperature :-) The walk around Granite Is is very fine. Allow all day.

  • Waterfall Gully. Another cool oasis. Can walk up to the waterfalls. Allow a few hours.

  • Tour Down Under, 20-27 Jan. More for dad than the kids.

  • Council library.

  • Carrick Hill. How the other half lived a long time ago.

Let's review.

Dirty tricks. Pollies unable to simply show up. Slapping journalists. Liberal Party loses government, John Howard loses his parliamentary seat and thus leadership of the Parliamentary Liberal Party, Peter Costello does not nominate for leadership of the Party and intends to retire from Parliament. Worst of all, the journalist's journalist Matt Price dies.

My call about Nick X getting 1.5 quotas was spot-on. The ALP actually did poorly in South Australia, not picking up the southern suburbs of Greater Adelaide which they could have been expected to win. There's no national reason to explain that; local factors don't help either: one seat had a poor candidate, one seat had an excellent candidate; which leads to state factors. Maybe state factors do determine federal votes when all governments are the same party?

I think we're about to see the Mother of All Razor Gangs go through Federal spending. These new lads and lasses cut their teeth in state government administration. I think they've been appalled at "government spending like a frequent flyer programme" rewards for loyalty schemes of the late Howard era.

Giving a presentation at the Australian 2007 IPv6 Summit on AARNet's experiences with IPv6. Only a half hour slot, so I'll do a handout as well -- I find this works well as the technical people read the paper and thus don't feel like the presentation glossed over a lot of material (which of course it does, since 30m isn't time enough to teach anyone anything).

Interesting issue when writing slides. I don't like them at the best of times. But I've given a fine talk without anything on the screen and the feedback forms mainly all complained about the lack of slideware. I went to a talk once by Philip Lynch and he just had generic photos which he changed once every five minutes or so -- I might have a few more slides since I'm not as good a speaker as Phil. We'll see how it goes down with the crowd.

The kids got all dressed up, E looked very fine as a vampire. Then they all trooped off to knock on the doors of their friends. Large amounts of lollies collected. Stomach aches complained of (surely there's no connection!).

Had a huge bag near our door should adventurous older kids wander down our street and be attracted by the ghost and spiders on the front gate. There were a few callers. A nice time was had by all.

As usual, I find myself holding the completely different view that I had before we had kids. B.K I thought Halloween was a horrible US import. A.K I think that it does no harm, so let them dress up and have some fun.

I am please to inform you that we have accepted your talk below for the 2008 Sysadmin Miniconf.

Response to call for papers for 2008 sysadmin miniconf


Tuning hosts for network performance.


The bottleneck for network performance used to be transmission capacity. Huge amounts of capacity can now be had for moderate cost. The bottleneck has now moved to the host connected to the network and to the network protocols and their tuning.

This presentation gives Linux system administrators information to identify practices which lead to poor network performance. Common fault scenarios and the tools used to investigate those scenarios are explored.

The pros and cons of using Linux as a network middlebox are examined and a checklist of good practices for middleboxes are given.

Specific practices include: bandwidth-delay product and TCP buffer tuning; Linux buffer autotuning; congestion, link loss and TCP performance; common causes of link losses; choice of TCP algorithm, performance and fairness; applications design. Tools include: what do ping and traceroute actually measure; using iperf and ttcp, using Web100 kernel patches.

Middlebox issues include: participating in the control plane; anti-DoS measures; allowing fault diagnosis; queuing; minimising jitter; fairness; concurrent flow effects.

Add Iban Mayo of Saunier Duval-Prodir, placed 16th. Doing EPO.

Werner Franke has reviewed the Operación Puerto documents and says of Contador on ZDF TV: "He took insulin, HMG-Lepori, a hormone to stimulate the secretion of testosterone and also a product for asthma called TGN. In brief, I have before my eyes a protocol for doping." Contador disagrees.

Dick Pound of WADA told the UK's Daily Mail that he wants to investigate further, as the Spanish inquiry did not investigate Contador any further once it found that Contador had done nothing criminal in Spain. WADA and Contador's old teammate Jörg Jaksche may do a deal to decrease Jaksche's ban from cycling in return for the identity of "AC" in the doping plans of Eufemiano Fuentes. The name "AC" in the file has "nothing" against it, but the initial's mere presence in the files shows a plan, even if the that month's doping was being halted before some event.

Fuentes' files also contain the names of soccer and tennis players, a scandal yet to fully develop.

Meanwhile, Vinokourov complains via his lawyers: "I have always raced clean. These test results simply make no sense." The B sample exists so that these complaints can be backed by fact -- Vinokourov can choose the lab and oversight the testing. But his B sample is positive too. Looks like we'll be seeing Landis's "unique physiology" claims next. I wonder how many cyclists can have a unique physiology?

UK prof Julian Savulescu argues it is time to regulate doping. He obviously missed the crowd booing Rasmussen when he received the yellow jersey. Anyway, doping is regulated now; what makes him think laxer regulations are going to be adhered to if breaking them still gives an advantage?

Before he retired, Ian Thorpe wanted a blood bank for athletes. This blood could be tested in the future and an clean athlete could have their record stand untainted by accusations of doping which were based only upon the athlete's extraordinary performance. It's time.

So I got sucked in again, after last year's disappointment with watching for three weeks and then the Landis scandal.

One by one the people I admired most in the race have proved to be cheats. I thought perhaps I was cursing them with my support. But this can't be so, because a moment's thought gives this list of people who were meant to race in Le Tour 07 and found to be doping: Ullrich, Basso, Jaksche, Mazzoleni, Sinkewitz, Kessler, Moreni (taking out the Cofidis team), Vinokourov (taking out the Astana team, which must please the Tour organisers greatly since least year Astana forced their way into the race against the organisers' wishes), Rasmussen.

All Tour winners before 1966 were doping. If you make a list of the tour winners since 1966 and cross off those with some proven connection to doping you get only: LeMond 1986, 1989, 1990; Hinault 1978, 1979, 1981-2, 1985; Van Impe, 1976. Let's be generous and add Armstrong 1999-2005, since his positive test seems to have been a prescription paperwork error.

Merckx says "for me, that's the end of cycling." And with the lists above, you can see his point.

You have to feel sorry for the team. Imagine being in Rabobank. You can't blame Menchov for throwing in the towel, after all of his efforts to advance Rasmussen and the cost of his own chances.

And still the cloud of Operación Puerto hangs over Contador; even with the Spanish court saying he was not involved.

Can't get excited after least year's disappointments. Phil Ligget's efforts to cast the sport in a good light are merely annoying rather than courageous.

It's not to much to ask that people compete fairly. For some reason cyclists and AFL footballers think otherwise.


Glen Turner

August 2017

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