All CORNET nodes currently have private IP addresses, and are behind the CORNET firewall. However, the ssh port for each individual node is still directly accessible through the firewall. To access the CORNET nodes you must ssh to the CORNET gateway, 128.173.221.40, using a specific port that is unique to each CORNET node. The CORNET gateway redirects the ssh traffic to the appropriate CORNET node ssh server.
For information on the physical locations of the RF portion of the node, see here: CORNET Node Location and Status Information
The port list is as follows, where NodeX-Y refers to node Y on floor X:
| Floor 1 | Port | Internal IP |
| Node1-1 | 7001 | 192.168.1.11 |
| Node1-2 | 7002 | 192.168.1.12 |
| Node1-3 | 7003 | 192.168.1.13 |
| Node1-4 | 7004 | 192.168.1.14 |
| Node1-5 | 7005 | 192.168.1.15 |
| Node1-6 | 7006 | 192.168.1.16 |
| Node1-7 | 7007 | 192.168.1.17 |
| Node1-8 | 7008 | 192.168.1.18 |
| Node1-9 | 7009 | 192.168.1.19 |
| Node1-10 | 7010 | 192.168.1.20 |
| Node1-11 | 7011 | 192.168.1.21 |
| Node1-12 | 7012 | 192.168.1.22 |
| Floor 2 | Port | Internal IP |
| Node2-1 | 7013 | 192.168.1.23 |
| Node2-2 | 7014 | 192.168.1.24 |
| Node2-3 | 7015 | 192.168.1.25 |
| Node2-4 | 7016 | 192.168.1.26 |
| Node2-5 | 7017 | 192.168.1.27 |
| Node2-6 | 7018 | 192.168.1.28 |
| Node2-7 | 7019 | 192.168.1.29 |
| Node2-8 | 7020 | 192.168.1.30 |
| Node2-9 | 7021 | 192.168.1.31 |
| Node2-10 | 7022 | 192.168.1.32 |
| Node2-11 | 7023 | 192.168.1.33 |
| Node2-12 | 7024 | 192.168.1.34 |
| Floor 3 | Port | Internal IP |
| Node3-1 | 7025 | 192.168.1.35 |
| Node3-2 | 7026 | 192.168.1.36 |
| Node3-3 | 7027 | 192.168.1.37 |
| Node3-4 | 7028 | 192.168.1.38 |
| Node3-5 | 7029 | 192.168.1.39 |
| Node3-6 | 7030 | 192.168.1.40 |
| Node3-7 | 7031 | 192.168.1.41 |
| Node3-8 | 7032 | 192.168.1.42 |
| Node3-9 | 7033 | 192.168.1.43 |
| Node3-10 | 7034 | 192.168.1.44 |
| Node3-11 | 7035 | 192.168.1.45 |
| Node3-12 | 7036 | 192.168.1.46 |
| Floor 4 | Port | Internal IP |
| Node4-1 | 7037 | 192.168.1.47 |
| Node4-2 | 7038 | 192.168.1.48 |
| Node4-3 | 7039 | 192.168.1.49 |
| Node4-4 | 7040 | 192.168.1.50 |
| Node4-5 | 7041 | 192.168.1.51 |
| Node4-6 | 7042 | 192.168.1.52 |
| Node4-7 | 7043 | 192.168.1.53 |
| Node4-8 | 7044 | 192.168.1.54 |
| Node4-9 | 7045 | 192.168.1.55 |
| Node4-10 | 7046 | 192.168.1.56 |
| Node4-11 | 7047 | 192.168.1.57 |
| Node4-12 | 7048 | 192.168.1.58 |
For example, to access Node 1-3, ssh to trac.cornet.wireless.vt.edu (128.173.221.40) using port 7003.
FCC Authorization
CORNET operates under the authorization of FCC designated call sign WF2XRP All users are responsible for ensuring that their research is conducted within the limitations of the above license. The permitted bands of operation are listed in the table below:
| Lower Bound (MHz) | Upper Bound (MHz) |
| 138 | 144 |
| 150.5 | 156 |
| 157.45 | 161.575 |
| 162.0375 | 174 |
| 450 | 512 |
| 764 | 862 |
| 776 | 787 |
| 788 | 793 |
| 824 | 849 |
| 869 | 894 |
| 1850 | 1910 |
| 1930 | 1990 |
| 3400 | 3600 |
Accessing the network from Windows
From a windows machine, an SSH client is required in order to remotely access the CORNET nodes individually. A popular windows SSH client is PuTTY.
Accessing the network from Linux
From a linux machine simply issue the following command where the port is 7000 + the node # you want to log into.
# ssh -X <username>@128.173.221.40 -p <7000 + node#>
Note: the -X allows X11 forwarding for running X11 applications remotely.
For example, to login to CORNET node1-2 with the login name "testuser" do the following:
# ssh -X testuser@128.173.221.40 -p 7002
To login to CORNET node 1-3 with the login name "testuser" do the following:
# ssh testuser@128.173.221.40 -p 7003
Using X2GO as a CORNET virtual desktop
- On Linux
- If not already installed, run “sudo apt-get install x2goclient” in terminal
- Once installed, create new session in X2GO
- On Windows
- Install X2GO client from Link: http://wiki.x2go.org/doku.php/download:start
- Choose "Custom Desktop" then "Command:MATE" and the port relating to the node you wish to access, based on the previously provided table
- An example set-up session
In the X2GO session window, the following fields need to be changed:
Login: change to username provided by CORNET admin
In the X2GO session window, the following fields can be changed:
Session name: can be any name, typically named Cornet <node> for simplicity
SSH port: change to access desired CORNET node based on tables listed on wiki
Obtaining Remote Access Login Information
To obtain login credentials for the CORNET nodes, please email the CORNET administration at [vtcornet@…]
Working from your User directory
Each registered user receives a folder on a dedicated NFS drive which allows them to store and access code locally. Each CORNET node mounts the NFS directories at boot time and you may access your directory on each node at /users/<username>.
In the interest of open and collaborative development, each user has read access to the other user folders and read/write access to their own folder. You may upload files into your NFS directory in the following way:
- Verify you can login to the node by following the above ssh procedures. - Change to your user directory:
# cd /users/<username>
- Open a new local shell (ctrl+shift+t in Ubuntu) - Change to the directory which contains the files to copy:
# cd /path/to/myfiles
- Use the SCP command to copy the local directory "mydir" to the remote node:
# scp -r -P [Port] mydir *my_login*@trac.cornet.wireless.vt.edu:/users/<username>
Note: the -P MUST be capitalized. -r means recursive copy, and is used for copying directories. You do not need to use -r to copy single files.
Once you have copied the files to your user directory, verify the copy was successful by issuing the "ls" command in the first shell you opened. You may now directly work with the files in your user directory.
Time Synchronization
All nodes are time synchronized with NTP. , but it is not enabled by default.
Node Software
Each node contains the following software:
- Ubuntu Linux 14.04 LTS
- GNU Radio Companion 3.7.6
