ModeemiWiki

Hi! welcome to our workshop! Today we'd like to show a few things that you can do with computer networks!

1. Set up the static IP addresses
   1. Device IP: 192.168.1.x/24 (each participant has number from 1 to 254)
   2. Mask: 255.255.255.0
   3. Gateway IP: 192.168.1.253
2. Open the wireshark
   1. use an “arp || icmp” as in a filter (that will show only ARP and ping messages)
3. Ping the other people IPs
4. Take a look at the ARP table in computer
   1. command “arp -a” in windows
   2. command “arp -n” in linux (net-tools have to be installed)

Local area network (4 participants)

The following points will be discussed:

1. IP addresses (IPv4)
   1. Gateway
   2. Broadcast
   3. Network
2. Local network
   1. Set it up (static)
   2. Connect computers together
   3. Take a look at packets (wireshark)
3. ipinfo.io
4. jodies.de/ipcalc

Set up following stuff:

1. Set up network IP addresses (IPv4)
   1. First router - 10.1.1.0/24
   2. Second router - 10.1.2.0/24
   3. Third router - 10.1.3.0/24
2. Set up DNS server for AdGuard
   1. https://adguard-dns.io/en/public-dns.html
   2. check if ADs work?

1. Install wireguard in openwrt
2. Then set it up with helpful instructions from this page

1. we will find commands on the fly
   1. ip route add
   2. ip addr add
   3. and others:D

1. VPN project - two sites

1. first with 10.1.1.0/24 network, VPN server
2. second with 10.1.2.0/24 network, VPN client
3. first has 10.1.3.1/30, second has 10.1.3.2/30

Server:

[Interface]
PrivateKey = yourPrivateKey
Address = 10.1.3.1/30
ListenPort = 51820
PostUp = ip route add 10.1.2.0/24 via 10.1.3.2

[Peer]
PublicKey = OtherpartyPublicKey
AllowedIPs = 10.1.2.0/24, 10.1.3.2/32

Client:

[Interface]
Address = 10.1.3.2/30
PrivateKey = yourPrivateKey
PostUp = ip route add 10.1.1.0/24 via 10.1.3.1

[Peer]
PublicKey = OtherPartyPublickey
Endpoint = publicIP:51820
AllowedIPs = 10.1.1.0/24, 10.1.3.1/32
PersistentKeepalive = 21

Generate private and public key for VPN server

wg genkey | tee privatekey | wg pubkey > publickey; cat publickey; cat privatekey