FriendFeed’s response about del.icio.us feeds not updating

FriendFeed

Ross Miller at FriendFeed responded to my question about FriendFeed del.icio.us feeds not updating. It seems del.icio.us is blocking mass spidering of their site.

Ross’s email:

“Hi Sol, del.icio.us places restraints on our ability to crawl their site. So if for some reason the item is missed, it becomes very hard for us to retrieve the del.icio.us link. Unfortunately for now the refresh button is your best option when this happens. Sorry for the inconvenience and we hope to get this resolved with del.icio.us soon.”

Looks like this is a restriction on del.icio.us’s end.

Crossing the streams – large numbers of Twitter updates

Chris Bilson (@cbilson) had a good description regarding my post about Twitter’s scaling/architecture challenge.

Kevin Rose and Leo Laporte tweet at the same time = crossing the streams”

I dunno if Proton Packs have exponential load challenges, but the end result for a server can feel similar. Is my post I pointed out that Twitter has to determine delivery options and potentially deliver between 100 million and 1 billion updates per day.

But that’s in a day. 1 billion messages in a day are a piece of cake when spread over 24 hours. What if 1 billion messages have to be delivered in an hour? Or all at once?

Take my list of the top-10 Twitter accounts and imagine them all at TED, WWDC, Google I/O, or your local unconference. These ten users, if each sends an update around the same time create 321,928 messages that need delivery (total number of followers for top-10 accounts). This is an awesome amount of message delivery. If those ten users live-blog or get conversational and send ten updates in an hour… 3,219,280 (again, that’s from only 10 users).

I don’t illustrate this to state it’s these power user’s fault. Absolutely the opposite. They’re generating amazing amounts of traffic, which is a wonderful thing, and the algorithms are the problem.

It’s possible to optimize algorithms and modify systems for maximum performance. I bring up Twitter’s challenges because I’m wondering if this is a challenge beyond present day computing.

To open some minds, here’s an impossibility often overlooked: Huge numbers in a deck of cards (just to show impossibilities can stem from small initial numbers).

Twitter’s one-to-many scaling impossible?

Twitter has been having all kinds of scaling challenges. There have been hundreds, if not thousands, of posts on the subject. Dave Winer pushed an idea for a decentralized Twitter (and has since admitted the power of Twitter is in its centrality). There is a single, simple, reason for Twitter’s challenges – Math is against them.

The facility of communication on the Twitter service is absolutely outstanding. I’ve written extensively about using it to receive an amazing amount of quality information in my series on flow.

I originally questioned the scaling ability of the service prior to SXSW, but when the service held up I went back to the drawing board to make sure my numbers were correct.

Before continuing, let’s establish the basics about the service so the math will make sense…

  • Each Twitter account can follow any other Twitter account (bear with me and forget those accounts with private updates).
  • Messages travel in one direction, from the updater to the follower.
  • Each account has updates from other accounts it follows placed in its timeline.
  • A Twitter account can selectively receive pushed updates immediately via instant messenger and SMS in addition to having an update added to its timeline.
  • An update added to an account’s timeline may or may not be push based (lets assume it’s demand driven, or pull based).
  • An update sent to an account from an account denoted as SMS or IM announcement is push based (there is no other way to send an update – it must be actively pushed from the server).
  • The mere possibility of an update needing to be pushed requires the system to check with each follower’s settings, thus requiring analysis of each follower for each update.

A warm-up equation

If there are one hundred (100) users and each user follows ten (10) fellow users, and each user sends ten (10) updates per day, assuming all updates are push-based, how many updates are sent?

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Mobile phone GPS a security risk? Only to those who follow you

Steven Hodson, in a post over on Mashable, describes security risks and the waste of information that mobile phone GPS use brings (when pinpointing and announcing our locations). He poses some extremely valid points in regards to announcing one’s geolocation via Twitter, Brightkite, or FriendFeed being useless noise.

Telling people via a highly conversational medium such as instant messaging or an SMS text that you are currently at 13th St and Ash Lane is nothing more than noise. It’s a waste of precious conversation. To a few of your closer friends it may be relevant, such as a buddy that would meet you for coffee. But for the masses, it is unimportant and you’re guilty for wasting their time.

I’m guilty of this lately. I’ve been trying various mobile phone GPS services. It’s been fun and interesting, but I’m in agreement with Steven about this announcement being a waste (at least if it’s without background information). Steven doesn’t mention it, but my thought on optimal geolocation announcement is in a widget placed on one’s blog. It’s there for interested followers, but not intrusive or annoying.

But that’s where we agree. He describes broadcasting one’s geolocation as a security risk and I strongly disagree. Yes, there are some situations where it is. US soldiers in Iraq will not benefit from this feature. Folks in witness protection programs, runaways, victims of domestic violence, those being stalked, cheating spouses, and those in organized crime probably won’t either.

The typical citizen without conflict is not at risk. It’s easy to figure out when someone is normally at work, so knowing an optimal time to break in to someone’s home is already simple. It’s easy to find a person in a public place, so it’s already easy to find the optimal time to commit physical harm.

Note: If one is being stalked or believes him or herself to be in a situation where announcing location is dangerous, it’s simple to turn the feature off.

As I’ve said before, people are inherently good. They don’t go around looking for someone to damage or rob. There are some people who commit these crimes. These people use crow-bars instead of Facebook, and are stopped by alarm systems and deadbolts rather than a lack of geolocation data.

Mobile Phone GPS – Where are we going?

BlackBerry 8800 GPS

Most smartphones slated for release over the next 12-months include a GPS receiver, built in. After that, it will be a marked failure to not include a GPS in a phone. The functionality that comes with GPS is outstanding – mapping, directions, location based experiences, etc. We’re about to enter an age of advancement in technological capabilities that we’re just beginning to imagine.

Consumers are moving to smartphones. The hottest smartphones (iPhone 3G, BlackBerry Bold 9000, most of Nokia’s Symbian and HTC’s Windows Mobile offerings) all include GPS and an exposed API for developing applications utilizing their hardware. Anything people can conceive of for location based mashups will be coming (more on these mashups in later posts)…

trackinghistory

Here’s a first application…

BlackBerry is a leader in mobile phone GPS. Recently a few services that announce the location of one’s phone emerged. Initially these were billed as a sort of low-jack for one’s phone, a security service for the insecure (or those who want to spy on their kids, etc).

I decided to try a few of these. Most felt slimy, like, “you always know where your phone is, and you could also know where your wife is!” … I don’t know about you, but my phone is loyal and doesn’t run off with strangers… And I trust my wife far more than a phone.

My goal with trying these services was to mash Twitter, Pownce, Facebook, and other social networking services with my location. Such a mashup will allow me to share my real-time location with all friends. I came across BlackberryTracker.com. Much like the others, the idea is to provide you with the location of your phone. However, they have something the other’s don’t… Facebook and Google Earth integration (as well as a drop-dead-simple semi-RESTful API).

Friends can pinpoint me down to the meter on my Facebook profile, updated every 30 seconds. To be honest, it feels strange to openly publish this data. Security, and lack thereof, has us believing we shouldn’t share such information. But this fear is caused by the exception and not the rule. And in reality, my location in public isn’t private. Additionally, there are laws and common courtesies we live by, and I trust that people are inherently good.

Soon these services will be in the mainstream. Everyone will be able to pinpoint the location of anyone. Let me emphasize that… Soon everyone will be able to pinpoint the location of anyone. Not publishing your location will be like not having a mobile phone.