# Topology XML File This section describes the topology file format, used by the TADS to load the abstracted view of the local provider. The reference file for this description is ``` target/conf1wayTest/network1.xml ``` The main tag of the file is **network** that can include multiple **domains**, each domain represents a provider. ```xml ``` In this case the network topology includes two providers. The first part of the each domain contains some general information: - **domain_id**: the AS number of the domain represented in IPv4 format - the **reachability_entry**: that summarizes the prefix network for the provider (IPv4 network prefix and mask) - **it_resources**: here the information related to overall IT resources availability is described considering - **controller_it**: the entry point for 5GEx orchestration - **cpu**: overall available CPUs - **mem**: overall available memory - **storage**: overall available storage ```xml 0.0.0.1 172.16.101.0 24 https://openstack.5Gex.com/url 100 100Gbyte 100Tbyte ``` Then the file is organized considering a list of nodes and a list unidirectional links. Each node is represented with a tag **node** and is identified with an IPv4 id called **router_id** ```xml 172.16.101.101 172.16.101.102 172.16.101.103 172.16.101.104 ``` In the reference case 4 nodes are considered. Each link is identified by the tag **edge**. The link description include: - **source**: the source node of the link, identified with the pair **router_id** and interface id, **if_id** - **destination**: the destination node of the link, identified with the pair router_id and interface - **TE parameters**: several possibilities are available, in the considered example the focus was on - unidirectional link delay - minimum experienced delay - maximum experienced delay ```xml 172.16.101.101 1 172.16.101.104 1 99 23 250 ``` For setting up default TE parameters for all the network links, the **edgeCommon** tag is used. ```xml 99 23 43 1 102 802 500 436 ```