Troubleshooting Methodologies and Tools B1 thu thap dau hieu su co B2 khoanh vung va co lap B3 khac phuc su co Transpot //NAT ACL Network //ping den router, gateway, xem mang internet co mat khong Datalink //PPP, Frame Relay Loi tang 1 //lam hieu nang giam, mat ket noi, CPU tang cao, ... ... Continue Reading
Broadband Services DSL //Khong bi chia se toc do Cable //cap truyen hinh chia nho luu luong cho so luong nguoi su dung, can modem rieng de dieu che DSL //cung 1 duong day co the tach ra 2 dich vu rieng la dien thoai va internet microfiltter //tach duong day la lam 2 spliter //ho tro viec dieu che tach voice va dien thoai Broadband Wireless VPN ... Continue Reading
Doi tuong can bao mat: he thong mang bi mat //thong tin du lieu chi nguoi dung duoc phep duoc truy cap toan ven //thong tin khong bi sua doi san sang/kha dung //he thong van hanh lien tuc 24/24 B1 tan cong thu thap, thu thap tat ca thong tin lien quan den he thong B2 liet ke va loc ra thong tin co ich B3 su dung phan mem ho tro de truy cap vao he thong B4 nang quyen ... Continue Reading
DHCP Manual Allocation //tu gan IP bang tay cho thiet bi Automatic Allocation //Cap IP tu dong cho may nao se mai mai khong thay doi IP - no lease Dynamic Allocation //Cap dong dia chi IP DHCP Discover - Broadcast //Di hoi trong mang may chu DHCP DHCP Offer //Dua thong tin IP ma DHCP quan ly DHCP Request - Broadcast //Gui ban tin yeu cau cap IP DHCP ACK/Pack //Gui ... Continue Reading
ACCESS LIST Tuong lua nam o mang EDGE trong kien truc mang doanh nghiep Dam bao an toan cho tai nguyen ben trong bang cach giam sat traffic ca trong va ngoai Firewall cung/mem Cong nghe Firewall packet filtering //loc goi tin - chu yeu tang 3 va 1 it tang 4 - khong chan duoc virus Statefull // loc len den tang 5 giam sat luon ca phien ket noi application ... Continue Reading
VC SVC //kenh ao dong, khi co nhu cau truyen thi moi dam phan va thiet lap kenh PVC //kenh thuong truc, co dinh duoc tao san DLCI 0-15 // 0: ban tin dac biet ANSI LMI 16-1007 //thuong su dung 1008-1024 // 1019-1022: Multicast 1023..................... 2 bytes 6 bit DLCI 1 bit C/R //khong su dung, bo qua co che hoi dap X25 1 bit EA //truong mo rong khi can thiet 4 ... Continue Reading
The Evolving Enterprise Small Office (Single LAN) (SOHO Single Office Home Office) Campus (Multiple LANs) //doanh nghiep Branch (WAN) //cac chi nhanh doi tac lam viec ben ngoai Distributed (Global) //mang ket noi toan bo tai nguyen may tinh tren toan cau The Enterprise Architecture Enterprise Campus Architecture Enterprise Edge Architecture //mang vanh dai, ... Continue Reading
Wifi //ten goi khac cua Wireless LAN (WLAN) WiMAX 802.16 //cong nghe khong day dien rong Why Use Wireless //di dong Client and Access Point Association Probing Authentication Association Wireless LAN Security Wireless LAN Security Threats Man-in-the-Middle Attacks Denial of Service Configure Wireless LAN Access ... Continue Reading
Layer 2 redundancy Types of Traffic Known Unicast //frame unicast dia chi mac dich trong bang CAM Unknown Unicast //dia chi mac khong ton tai trong bang CAM Multicast //truyen cho 1 nhom Broadcast //truyen cho tat ca Issues with Redundancy Layer 2 Loops Broadcast Storms Duplicate Unicast Frames MAC address table instability Spanning Tree ... Continue Reading
Introducing Inter-VLAN Routing Traditionnal Inter-VLAN Router on-a-stick //subinterface chia cong vat ly ra nhieu cong nho, moi cong lam mot gateway cho 1 vlan (config)#interface fa0/0 (config-if)#no shutdown (config)#interface fa0/0.10 //thuong . theo vlan id (config-if)#encapsulation dot1q [vlan id] (config-if)#encapsulation dot1q 10 (config-if)#ip address ... Continue Reading
