How to Start BGP Routing Projects Using MATLAB

To start Border Gateway Protocol (BGP) using MATLAB which is an essential protocol that designed for routing among the autonomous systems (ASes) on the Internet. To execute or replicate the BGP routing can be supported to know the routing strategies, path selection, and the distributed routing systems behavior in MATLAB.

Below is a detailed stepwise method to get started:

Steps to Start a BGP Routing Project in MATLAB

  1. Understand BGP
  • Purpose: BGP is a path-vector protocol to swap routing data among the ASes.
  • Core Features:
    • Path Selection: According to the attributes such as AS-path, local preferences, and next-hop, select the route.
    • Policies: It impacts the route selection and advertisement.
    • Stability: Utilises approaches such as route flap damping for stability.
  1. Set Project Objectives

Describe the project’s goals like:

  • Replicate the BGP path selection and route propagation.
  • Examine the effect of routing strategies.
  • Design AS-level topologies including routing decisions.
  1. Define Network Topology

Design the Internet like graph in which:

  • Nodes: Denote the ASes.
  • Edges: It specifies BGP peering relationships such as provider-customer, peer-to-peer.

Example: Adjacency Matrix

% Define adjacency matrix for AS-level topology

adjMatrix = [

0 1 0 0;

1 0 1 1;

0 1 0 1;

0 1 1 0

];

% Visualize the AS topology

G = graph(adjMatrix, ‘upper’);

plot(G, ‘NodeLabel’, {‘AS1’, ‘AS2’, ‘AS3’, ‘AS4’});

title(‘AS-Level Network Topology’);

  1. Define BGP Attributes

Describe the routing attributes for every path:

  • AS-Path: Set of ASes the route passes through.
  • Local Preference: It gives precedence for routes in an AS.
  • Next-Hop: The next AS transmitting traffic.
  • Multi-Exit Discriminator (MED): It is designed for intra-AS route selection.
  1. Simulate Path Advertisement

We need to mimic how ASes broadcast routes to neighbors and choose paths.

MATLAB Implementation of Route Advertisement

function [routingTable] = bgpAdvertise(adjMatrix, srcAS, destAS)

numASes = size(adjMatrix, 1);

routingTable = cell(1, numASes);

% Initialize routing table for the source AS

routingTable{srcAS} = {srcAS};

% Advertise routes to neighbors iteratively

for iter = 1:numASes

for i = 1:numASes

if ~isempty(routingTable{i})

% Advertise to neighbors

neighbors = find(adjMatrix(i, 🙂 > 0);

for n = neighbors

newPath = [routingTable{i}, n];

if isempty(routingTable{n}) || length(newPath) < length(routingTable{n})

routingTable{n} = newPath;

end

end

end

end

end

end

Example Usage:

srcAS = 1;

destAS = 4;

routingTable = bgpAdvertise(adjMatrix, srcAS, destAS);

fprintf(‘Routing Table:\n’);

for i = 1:length(routingTable)

fprintf(‘AS%d: %s\n’, i, mat2str(routingTable{i}));

end

  1. Simulate Path Selection
  • Execute the decision progression of BGP:
    1. It selects routes including highest local preference.
    2. Choose the shortest AS-path.
    3. Utilise the lowest MED.
    4. Desire routes that are got knowledge from the nearby neighbor.

Path Selection Example:

function selectedPath = bgpPathSelection(paths)

% Paths is a cell array of potential routes

% Select the best path based on BGP decision process

if isempty(paths)

selectedPath = [];

return;

end

% Sort by path length (AS-path length)

paths = sortrows(paths, @(p) length(p));

% Return the first path (shortest AS-path)

selectedPath = paths{1};

end

  1. Simulate Routing Policies

We can execute the routing strategies such as:

  • Prefer Customer Routes: Routes get knowledge from customers is chosen through peers and providers.
  • Avoid Specific ASes: Eliminate the paths including specific ASes.

Example Policy Implementation:

function selectedPath = bgpPolicySelection(paths, preferences)

% Preferences: A struct with preferences like localPref, avoidAS, etc.

if isempty(paths)

selectedPath = [];

return;

end

% Filter paths based on policies

if isfield(preferences, ‘avoidAS’)

paths = paths(~contains(paths, preferences.avoidAS));

end

% Sort by local preference if specified

if isfield(preferences, ‘localPref’)

paths = sortrows(paths, @(p) preferences.localPref(getFirstAS(p)), ‘descend’);

end

% Select the first path after applying policies

selectedPath = paths{1};

end

function asNum = getFirstAS(path)

% Get the first AS in the path

asNum = path(1);

end

  1. Visualize Routes

Envision chosen paths at the AS topology graph.

Example:

% Visualize the selected path

selectedPath = [1, 2, 4]; % Example path

plot(G, ‘NodeLabel’, {‘AS1’, ‘AS2’, ‘AS3’, ‘AS4’});

highlight(plot(G), selectedPath, ‘EdgeColor’, ‘r’, ‘LineWidth’, 2);

title(‘BGP Selected Path’);

  1. Evaluate Performance
  • Convergence Time: Estimate duration to become stable after modernizes for the network.
  • Policy Impact: Experiment how routing strategies impact the path selection.
  • Scalability: Examine the performance for large AS-level topologies.
  1. Extend the Project
  • Simulate BGP Failures: Design link or node failures and then monitor the rerouting.
  • Implement Route Flap Damping: Minimize instability that is triggered by often route modifications.
  • Add Traffic Simulation: According to the chosen BGP paths, mimic data flows.

Complete MATLAB Code Example

Below is a comprehensive BGP routing simulation:

% Define adjacency matrix

adjMatrix = [

0 1 0 0;

1 0 1 1;

0 1 0 1;

0 1 1 0

];

% Advertise routes using BGP

srcAS = 1;

destAS = 4;

routingTable = bgpAdvertise(adjMatrix, srcAS, destAS);

% Display the routing table

fprintf(‘Routing Table:\n’);

for i = 1:length(routingTable)

fprintf(‘AS%d: %s\n’, i, mat2str(routingTable{i}));

end

% Select the best path using policies

paths = {[1, 2, 4], [1, 3, 4]};

preferences.avoidAS = 3; % Example policy to avoid AS3

selectedPath = bgpPolicySelection(paths, preferences);

fprintf(‘Selected Path: %s\n’, mat2str(selectedPath));

% Visualize the selected path

G = graph(adjMatrix, ‘upper’);

plot(G, ‘NodeLabel’, {‘AS1’, ‘AS2’, ‘AS3’, ‘AS4’});

highlight(plot(G), selectedPath, ‘EdgeColor’, ‘r’, ‘LineWidth’, 2);

title(‘BGP Selected Path’);

These guides will explain you how to start, simulate and estimate the Border Gateway Protocol (BGP) Routing Projects through given simplified approach in MATLAB environment. Let me know if you require additional BGP aspects and assistance to extend this project in another way.