Thinking about Activity Pub

Quoting Henrik Karlsson “A blog post is a very long and complex search query to find fascinating people and make them route interesting stuff to your inbox” 

Somewhat more specifically, we are looking for ways to work on distributed systems. Could be systems design, software development, or technical market opportunity analysis. Or something we haven’t found yet. 

A decentralized social media service is one angle of approach; the Activity Pub protocol might benefit from some rethinking of the server  implementation with the goal of enabling large scale. There’s a discussion of Takahē , which has different goals, and mentions of other server implementations here This focus on Activity Pub is of course prompted by the dramatic changes at Twitter under its new master, and the consequent increase in users and server implementations of Mastodon. 

Bruce Davie discusses what is meant by decentralization in this context “Mastodon and other applications in the fediverse are organizationally distributed. Each instance of a Mastodon server is run by a person or group who gets to make their own decisions both about how to run the service technically and on the policies that will apply to the instance.” 

Quoting Kiernan Christ writing for  Lawfare “Policymakers should be aware of the Fediverse, even though it currently has a much smaller user base than any mainstream social media company. Regulations developed to deal with the negative consequences of Big Tech may be ineffective or incompatible with decentralized services.” 

Lawfare blog 9 May 22

Bruce Davie 

Guide to Mastodon

Henrik Karlsson 

More about Mastodon

On Mastodon

Never waste a good crisis

The Scottish government has a committee, the Scottish Advisory group on Economic recovery  “to provide independent expert advice on supporting the sectors and regions of Scotland’s economy to recover from the impact of Covid-19”. I was asked to contribute to the consultation which took place last week (closing date 31 May)

Gathering together my responses, paraphrasing the questions, and adding a list of references : 

Q: What will be the shape and form of the recovery from the crisis and what will be the implications for the future growth and structure of the economy?

What are the opportunities to boost private consumption to stimulate the recovery ? 

Which aspects of regulation might be relaxed to stimulate growth ?

A: View from Silicon Valley :  The construction business is back in full swing.  Large companies (Facebook, Google, Cisco, Microsoft) have moved smoothly to Working from Home and are going to continue doing that. Their user conferences and most other conferences have changed to being remote only. Sectors of the economy which have been impacted most severely, which have laid off most people, are non-essential retail stores, followed by restaurants. 

There’s an opportunity for a dramatic re-think of the concept of the ‘working week’, following on from WFH and the income support which has happened.  4 day weeks, enabling more businesses to be open every day, with support for scheduling so that people can usually spend their days off with family and friends, would enable more people to have flexibility in their lives between paid and volunteer work.

Trying to stimulate growth in take out food and non-essential retail would be a mistake, although income support for the employees is critical. There are opportunities for employment in essential retail, which needs more people and hours to maintain distancing and cleanliness.  

Q: What are the medium- to long-term consequences of the lockdown on businesses, including loss of employees, debt overhang, loss of markets, reduced investment and unemployment? 

A: The medium to long term consequences can be very positive; there has been a forced acceleration of companies retraining their teams to work in a distributed, remote, highly digital world.  Doing this well and early can be a competitive advantage; Scottish companies could offer remote teams who deliver work all over the world without having to travel there.  

Q: What can be done now to ensure the transition to a wellbeing-oriented, inclusive economy on a transition to net zero ?

How can the wellbeing of the people of Scotland flourish and what are the environmental implications of the crisis?

A: Three big things : infrastructure investment in Internet communications; enabling conversion of office and retail space to insulated residential accommodation with room for WFH; rethink transport policies to encourage electric bicycle and economical small scale delivery and pickup for physical goods going to consumers.

  1. Provision of fibre for broadband network has been a political minefield and remains inadequate for WFH over much of the country. Private only provision has not been effective. Cellular networks are not an adequate substitute.  Sweden’s strategy, for “market-driven development, completed by public efforts” is worth emulating.  

There’s a proposal for the creation of a National Investment Authority (NIA) by Cornell University law professors Saule Omarova and Robert C. Hockett, worth considering for the Scottish Investment Bank.

  1. WFH, made possible by improved communication infrastructure, reduces commuting costs, which reduces pollution and energy use as well as saving time and frustration. Every effort should be made to encourage this to continue.  This implies that office space should be able to be converted into residential accommodation.  The collapse in non-essential retail is an opportunity to take advantage of those existing buildings, particularly in small towns where the high street has been hollowed out, to convert them for residential use, with requirements in building codes for insulation and heat pumps. 
  1. Continuing the reduction in vehicle traffic which happened in the lockdown while enabling people to have freedom of movement requires a system scale re-think. Encouraging cycling, particularly e-bike use (as in the Netherlands and Germany) for personal transport and local deliveries, would contribute to well-being. 


Call for views Sundar Pichai, CEO of Google and Alphabet Published May 26, 2020

Quantum computing

Snapshot, November 2019

State of the art summary, references and curated comments Scott Aaronson

Small companies

IonQ Trapped ion computing
PsiQ Silicon photonics
QCWare Software services
Rigetti Quantum cloud services
Xanadu Quantum photonic processors

Large companies
Honeywell Trapped ion Qbits

Upcoming conference San Jose 10 -12 December 2019

Consolidation in high capacity interface business

First Nividia announced it was to acquire Mellanox. Now Xilinx announces the acquisition of Solarflare. These are the two big sources of expertise in the high capability, high throughput Network Interface Card market.

When this sort of consolidation happens, it’s a signal to watch for one or more smaller players to emerge, potentially with expertise and money coming from the acquired companies, to develop the next state change in one of the often overlooked but critical enablers of the very large scale datacenters enabling cloud operational scale.

The competition is AWS, who have built their own ASIC, used in the NICs in the Nitro System. James Hamilton describes the system, used for I/O acceleration, security, and to implement a hypervisor.

February 2019
March 2019
April 2019

Edge fabric management, Facebook version


Omar Baldinado introducing the Facebook Networking @ Scale event, 22 May 2018

The event was held at the Computer History Museum.


To pick out one talk for attention, Niky Riga described the Edge Fabric which Facebook uses to configure and operate its equipment in PoPs, of which it has many hundreds, generally located in shared co-location space near to its users, so as to be able to serve content with lower latency than would be possible for direct service from the large data centers. This was a refresh of the material from an paper published in ACM Sigcomm, available here

These events are good for meeting new people involved with networking, and for meeting up with people whom one hasn’t seen for a while, without the effort of going to Nanog or IETF meetings.

Updating, 22 June 18, to add the link to the video archive of the talks.