Trong kien truc mang may tinh, neu Router duoc coi la "canh cua" ket noi the gioi ben ngoai thi Switch chinh la "ve binh" dieu phoi moi hoat dong ben trong. Tuy nhien, khong phai ai cung hieu ro ban chat ky thuat Switch la gi va tai sao no lai quan trong hon mot bo chia cong thong thuong. Bai viet nay se giai ma thiet bi nay duoi goc nhin chuyen sau cua mot chuyen gia mang.

1. Dinh nghia ky thuat: Switch la gi?

Switch (hay thiet bi chuyen mach) la mot thiet bi phan cung dong vai tro trung tam de ket noi cac thiet bi dau cuoi nhu may tinh, may in, server hay diem truy cap khong day (AP) trong cung mot mang cuc bo (LAN).

Ve mat ky thuat, Switch hoat dong tai Lop 2 (Data Link Layer) trong mo hinh OSI. Diem khac biet lon nhat giua Switch va cac thiet bi ket noi tho so the he cu chinh la kha nang xu ly du lieu dua tren dia chi MAC (Media Access Control). Thay vi gui tin hieu den tat ca cac cong mot cach mu quang, Switch tao ra mot kenh giao tiep rieng biet giua thiet bi gui va thiet bi nhan.

2. Co che van hanh: Tai sao Switch lai thong minh?

De hieu suc manh cua Switch la gi, chung ta can nhin vao cach no quan ly luu luong du lieu (traffic). Khi mot goi tin di vao Switch, thiet bi se thuc hien quy trinh sau:

Hoc dia chi (Learning): Switch ghi lai dia chi MAC cua thiet bi gui vao bang chuyen mach (MAC Address Table).

Dieu huong chinh xac: Khi thiet bi A gui du lieu cho thiet bi B, Switch tra cuu bang dia chi va chi mo "duong mon" du lieu giua hai cong tuong ung.

Che do song cong (Full-duplex): Nho co che phan tach luong, Switch cho phep cac thiet bi gui va nhan du lieu cung luc ma khong xay ra hien tuong xung dot (Collision), dieu ma cac bo Hub truoc day khong the lam duoc.

3. Cac dong Switch pho bien trong thuc te trien khai

Dua tren kinh nghiem 10 nam trong nghe, toi phan loai cac dong Switch dua tren muc dich su dung nhu sau:

Unmanaged Switch: Loai cam-la-chay (Plug and Play), phu hop cho ho gia dinh hoac van phong nho khong yeu cau cau hinh.

Managed Switch (Switch co quan ly): Cho phep can thiep sau vao cau hinh nhu chia mang ao (VLAN), uu tien bang thong (QoS) va bao mat cong (Port Security). Day la lua chon bat buoc cho doanh nghiep.

Switch PoE (Power over Ethernet): Kha nang vua truyen du lieu vua cap nguon dien qua day cap mang, cuc ky tien loi khi lap dat Camera IP hoac he thong Wi-Fi dien rong.

4. Tam quan trong cua viec lua chon Switch chuan

Viec hieu dung Switch la gi giup nguoi quan tri dua ra quyet dinh dau tu thong minh. Mot chiec Switch tot khong chi don thuan la tang so luong cong ket noi, ma con giup giam do tre (latency), tang tinh bao mat noi bo va dam bao he thong khong bi "treo" khi luu luong du lieu tang dot bien.

VTXVN la doi tac chien luoc cua nhieu hang san xuat thiet bi mang va thoai noi tieng, giup mang lai danh muc san pham da dang cho khach hang tai Thu do. Voi hon 10 nam kinh doanh bai ban, VTXVN khong chi ban san pham ma con cung cap giai phap vien thong toan dien. Con so hon 10.000 khach hang da phuc vu thanh cong chinh la loi cam ket danh thep nhat cho nang luc cung ung va che do hau mai chu dao ma chi co tai VTXVN.