I use kernel module geoip which not only blocks ssh attempts but any other service you want. (http , ftp.. ) on network level. It uses a kernel module , a csv with the ip country blocks and ip-tables.
So you can say : I only allow ssh from this country and block all the rest. It does a remarkable job
Slashdot Mirror
there is also redhat's OpenShift.
I use kernel module geoip which not only blocks ssh attempts but any other service you want. (http , ftp .. ) on network level.
It uses a kernel module , a csv with the ip country blocks and ip-tables.
So you can say : I only allow ssh from this country and block all the rest.
It does a remarkable job
and itworld.com has a nice set of 17 diffirent trackers on that page reported by gostery ...