Peering at the Internet’s Frontier: A First Look at ISP Interconnectivity in Africa Arpit Gupta, Matt Calder, Nick Feamster, Marshini Chetty, Enrico Calandro, Ethan Katz-Bassett In this talk we will talk about why we observe degraded Internet performance in Africa and discuss few possible solutions

BISmark: A platform to study home networks BISmark Gateway ISP Network Internet Home Network Modem Access link Custom OpenWrt firmware Netgear gateways – 650 MHz processor, 128 MB RAM Active and passive measurements in and out of home network

200+ gateways in 20+ countries (Dec 2014) Deployment 200+ gateways in 20+ countries (Dec 2014)

Motivation: Peering Introduces Significant Latency Marshini Chetty et al. ”Measuring Broadband Performance in South Africa” ACM Symposium on Computing for Development (DEV). Cape Town, South Africa. December 2013.

Better understanding of existing connectivity required Why Study Africa? High latency routing paths Broadband access is expensive Better understanding of existing connectivity required

Outline ISP interconnectivity within Africa Reasons for poor interconnectivity Possible solutions

Uncover ISP Interconnectivity Construct view of Internet paths within Africa Circuitous Routing Paths Identify crps and quantify their prevalence

Circuitous Routing Paths AS2 Europe/ US Africa AS1 AS3

How to Identify Circuitous Routing Paths? AS2 Europe/ US Africa AS1 AS3 Use traceroute probes

Use BISmark Routers to Run Traceroutes Represents performance behavior for end users Deployed in 17 South African homes Placed across 7 major regional ISPs

Destinations for Traceroute Probes M-Lab Servers Google Cache Nodes

Identifying Circuitous Routing Paths M-Lab J’Burg M-Lab Nairobi … 7, 196.44.0.74, 7.793, South Africa, AS16637 8, 196.223.22.24, 8.338, South Africa, Cape Town IXP 9, 41.164.0.243, 34.679, South Africa, AS36937 14, 196.24.45.146, 92.511, South Africa, AS2018 … 8, 209.212.111.201, 199.446, South Africa, AS16637 9, 195.66.225.31, 217.301, United Kingdom, London IXP (LINX) 10, 196.32.209.77, 201.569, South Africa, AS36944 14, 197.136.0.108, 368.107, Kenya, AS36914 Packets leaving the African Continent

Latency Inflation Inflated Latencies M-Lab J’Burg M-Lab Nairobi … 7, 196.44.0.74, 7.793, South Africa, AS16637 8, 196.223.22.24, 8.338, South Africa, Cape Town IXP 9, 41.164.0.243, 34.679, South Africa, AS36937 14, 196.24.45.146, 92.511, South Africa, AS2018 … 8, 209.212.111.201, 199.446, South Africa, AS16637 9, 195.66.225.31, 217.301, United Kingdom, London IXP (LINX) 10, 196.32.209.77, 201.569, South Africa, AS36944 14, 197.136.0.108, 368.107, Kenya, AS36914 Inflated Latencies

Outline ISP interconnectivity within Africa Reasons for poor interconnectivity Possible solutions

Reasons for Poor Interconnectivity Regional IXPs fails to keep local traffic local IXP Prevalence Failure because either: Local ISPs not present at regional IXPs, or If present, IXP participants don’t peer with each other

Fewer Participants at Regional IXPs ISPs prioritize connecting to European IXPs Fewer incentives to connect at regional ones KENET South Africa Kenya Liquid Telecom J’Burg IXP Kenya IXP

Missing Peering Links at Regional IXPs Most content not available locally Less incentives to peer with local ISPs South Africa Kenya KENET MTN MTN IS IS J’Burg IXP Kenya IXP

Outline ISP interconnectivity within Africa Reasons for poor interconnectivity Possible Solutions

Improving Latency Deploying additional local cache nodes Adding more peering links at regional IXPs

Adding More Cache Nodes Traceroute Probes between: BISmark Routers (eyeball) Google Cache Node in Uganda (content) Cache Node hosted by MTN Emulates scenario where content is placed in a nearby country Latency Improvements Inside Customer Cone BISmark Routers Addition of cache nodes provides limited benefits with missing peering links

Adding More Peering Links at Regional IXPs Simulated peering between all the participants at: J’burg IXP (JINX) Kenya IXP (KIXP) Emulates scenario where more ISPs connect and peer at regional IXPs Latency improvement up to 250 ms Δ ~ 250ms Latency Improvement Adding cache nodes improves latency performance and adding more peering links ensures that this benefit trickles down to more number of users Additional peering links  Significant latency improvements

Cache Nodes with Additional Peering Links Cache Nodes in Kenya (1-5) Two scenarios: Existing peering links Additional peering links Minimum latency between BISmark routers & cache nodes considered No Further Latency Improvements Additional peering links  Lesser number of cache nodes

Mismatch of Incentives Add More Cache Nodes Less Local Content Poor Interconnectivity Add More Peering Links

Users Not Getting What They Pay For Marshini Chetty et al. ”Measuring Broadband Performance in South Africa” ACM Symposium on Computing for Development (DEV). Cape Town, South Africa. December 2013.

Mobile Broadband: Higher Throughput Mobile vs fixed MyBroadband

Mobile Latencies Can Be More Variable BISmark

Summary Circuitous routing paths within Africa Adding more peering links and local cache nodes improves latency performances upto ~250 ms Better incentive mechanisms required

High Latency Paths within Africa Geographical Distance Latency Penalties: Ratio of observed and speed of light propagation latencies Darker blocks imply higher latency penalties High Penalties for routes to M-Lab server in Nairobi High Latency Penalties M-Lab Servers

IXP Prevalence Quantifies presence of IXPs for routing paths Similar to routing path prevalence Lower IXP prevalence observed for circuitous routing paths

Role of Regional IXPs M-Lab J’Burg M-Lab Nairobi High Regional IXP Prevalence No Regional IXPs M-Lab J’Burg M-Lab Nairobi