patches for proxy

hi all.

sorry i just want to know the role of patches in abap proxy.

beacause we got one scenario like basis guys have to do with n-1 patches for creating abap proxy but i couldnt understand wat the meaning of patches .

can any one help me in this expaling wat the role pf this n-1 patches for abap proxy.

waiting for your response.

bye.

regards.

seeta ram.