Dropbear is a lightweight SSH2 server and client, it's small and useful for embedded environment.
Server: dropbear (stripped size 110K in Mandrake Linux 10.0)
Client: dbclient (stripped size 99K in Mandrake Linux 10.0)
Server Setup
mkdir /etc/dropbear
dropbearkey -t rsa -f /etc/dropbear/dropbear_rsa_host_key
or
dropbearkey -t dss -f /etc/dropbear/dropbear_dss_host_key
or use dropbearconvert to conver openssh key to dropbear key
eg. dropbearconvert openssh dropbear /etc/ssh/ssh_host_rsa_key /etc/dropbear/dropbear_rsa_host_key
Dropbear's sftp support relies on OpenSSH sftp binary or similar
default path /usr/libexec/sftp-server describes in options.h