hello, everyone . hello,everyone. i am doing my design work now . I need to simulate the CSMA/CD . i am newer to ns. i have no idea now . i hope someone can give me some advice or direction . yours frank zhang ---------------------------------------------- ��ӭʹ�� 21CN �����ʼ�ϵͳ http://www.21cn.com Thank you for using 21cn.com Email system