Camera PoE vs WiFi: Nen chon loai nao?
Lua chon giua camera Power over Ethernet va WiFi la mot trong nhung quyet dinh quan trong nhat trong bat ky du an CCTV nao. Moi cong nghe deu co nhung uu diem ro rang -- day la cach chung so sanh va khi nao nen su dung tung loai.
Muc luc
Cach PoE hoat dong
Power over Ethernet (PoE) dung nhu ten goi cua no: mot cap Cat5e hoac Cat6 Ethernet duy nhat truyen dong thoi du lieu mang va nguon dien den camera. Dieu nay loai bo nhu cau su dung bo cap nguon rieng cho tung camera, giup don gian hoa viec lap dat dang ke.
O phia nguon, switch PoE hoac bo tiem nguon PoE cung cap dien cung voi du lieu. Camera tieu thu luong dien can thiet tu cap, thuong tu 8W den 25W tuy thuoc vao model va cac tinh nang nhu xoay-nghieng-zoom, bo suoi hoac den hong ngoai IR.
IEEE 802.3af (PoE)
Tieu chuan PoE goc cung cap toi da 15,4W moi cong. Dieu nay du cho hau het cac camera IP co dinh, bao gom ca nhung camera co den LED hong ngoai tich hop. Phan lon camera giam sat hien co tren thi truong nam trong ngan sach cong suat nay.
IEEE 802.3at (PoE+)
Tieu chuan mo rong cung cap toi da 25,5W moi cong. Can thiet cho camera PTZ, camera co bo suoi tich hop cho thoi tiet lanh cuc doan va den hong ngoai cong suat cao can phu song khoang cach tren 50 met.
Do dai cap toi da: 100 met
Quy cach Ethernet gioi han do dai cap o 100 met (328 feet). Vuot qua khoang cach nay can bo mo rong PoE (repeater), co the truyen tin hieu them 100 met moi thiet bi, hoac chuyen sang cap quang voi bo chuyen doi phuong tien.
Quan ly nguon dien tap trung
Toan bo nguon dien duoc quan ly tu mot noi -- switch PoE hoac NVR co cong PoE tich hop. Ban co the giam sat muc tieu thu dien tren moi cong, khoi dong lai camera tu xa va bao ve moi thu bang mot bo UPS duy nhat trong tu vien thong.
Cach camera WiFi hoat dong
Camera WiFi truyen du lieu video khong day den router hoac diem truy cap chuyen dung bang cac giao thuc WiFi tieu chuan. Mac du thuong duoc quang cao la "khong day", nhung cac camera nay khong hoan toan khong co day -- chung van can nguon dien, du la o cam tuong, pin hoac tam nang luong mat troi.
Camera ket noi voi mang WiFi hien co giong nhu dien thoai hoac laptop, sau do truyen video den NVR, dich vu dam may hoac truc tiep den ung dung xem. Chat luong ket noi nay hoan toan phu thuoc vao cuong do tin hieu, nhieu va so luong thiet bi khac dang chia se mang.
Tieu chuan WiFi
Hau het camera su dung 802.11n (WiFi 4) hoac 802.11ac (WiFi 5). Cac model moi hon ho tro WiFi 6 (802.11ax) de hieu suat tot hon trong moi truong dong duc. Dai tan 2,4GHz cho pham vi xa hon nhung toc do thap hon; dai tan 5GHz cho toc do cao hon nhung pham vi ngan hon va kha nang xuyen tuong kem hon.
Yeu cau nguon dien
Moi camera WiFi can nguon dien rieng. Tuy chon co day bao gom bo cap nguon DC cam vao o dien gan do. Camera chay pin mang lai viec lap dat hoan toan khong day nhung can sac dinh ky (moi 2-6 thang). Tam nang luong mat troi co the keo dai tuoi tho pin vo han tai nhung vi tri co nhieu anh nang.
Pham vi tin hieu: 30-50 met qua tuong
Pham vi WiFi dien hinh la 30-50 met qua tuong, nhung thay doi dang ke tuy vao vat lieu xay dung. Gach va be tong giam pham vi toi 50% hoac hon. Ton, cach nhiet co giay nhom va khung kim loai co the han che pham vi nhieu hon nua. Pham vi ngoai troi co the dat 100+ met voi anten tot.
Chia se bang thong
Camera WiFi chia se bang thong voi moi thiet bi khac trong mang -- dien thoai, laptop, TV thong minh va thiet bi IoT. Mot camera 4MP duy nhat phat voi toc do 6Mbps co ve khong nhieu, nhung bon camera tieu thu 24Mbps bang thong WiFi, de lai it hon cho moi thu khac. Vao gio cao diem, chat luong video co the giam hoac ban ghi co the bi giat.
So sanh truc tiep
Bang so sanh nay tom tat nhung khac biet chinh giua camera PoE va WiFi trong cac khia canh quan trong nhat doi voi cac nha thiet ke va lap dat he thong CCTV.
| Yeu to | PoE | WiFi |
|---|---|---|
| Do tin cay | 99,9% thoi gian hoat dong | 95-98% (nhieu, mat tin hieu) |
| Do kho lap dat | Trung binh (can di day cap) | De (khong can di day) |
| Chi phi lap dat | Cao hon (cap, switch) | Thap hon (thiet bi toi thieu) |
| Pham vi cap/tin hieu toi da | 100m (co the mo rong) | 30-50m qua tuong |
| Bang thong moi camera | 100Mbps+ chuyen dung | Chia se, bien dong |
| Do tre | <5ms | 20-100ms |
| Nhieu | Khong co | RF, lo vi song, mang lan can |
| Kha nang mo rong | Tuyet voi (them cong) | Han che (8-15 camera moi AP) |
| Nguon du phong | UPS tap trung | Moi camera can nguon rieng |
| Chong pha hoai | Cao (khong co pin de an cap) | Trung binh (trom pin, nhieu tin hieu) |
Uu diem cua PoE chi tiet
Doi voi cac lap dat CCTV chuyen nghiep, PoE van la tieu chuan vang. Day la ly do tai sao cac nha lap dat co kinh nghiem uu tien ket noi co day cho cac he thong co dinh.
Do tin cay khong dao dong
Ket noi Ethernet co day khong bi nhieu tin hieu, vung chet hay mat ket noi. Khi cap da duoc dau noi va kiem tra, ban co the ky vong hieu suat on dinh trong suot thoi gian su dung. Khong bi mat tin hieu khi hang xom bat lo vi song, khong bi suy giam khi troi mua va khong bi dao dong khi cac thiet bi khac ket noi vao mang.
Nguon dien tap trung voi mot UPS duy nhat
Dat mot UPS duy nhat tai switch PoE va moi camera trong he thong deu duoc bao ve khoi mat dien. UPS 1500VA co the duy tri switch PoE 16 cong trong 30-60 phut khi mat dien. Voi WiFi, ban se can pin du phong rieng cho tung camera -- khong thuc te va ton kem.
Duong cap dai: 100m tieu chuan, 200m+ voi bo mo rong
Gioi han 100 met Ethernet bao phu thoai mai hau het cac toa nha. Cho khoang cach xa hon, bo mo rong PoE co gia re (khoang 30-50$ moi chiec) va them 100 met moi thiet bi. Doi voi trien khai tren khu vuc rong, mang loi cap quang voi switch PoE tai moi toa nha cung cap pham vi khong gioi han voi hieu suat dang tin cay.
Bang thong chuyen dung cho moi camera
Moi camera PoE co kenh 100Mbps chuyen dung rieng (hoac 1Gbps tren switch gigabit) den switch. Ngay ca camera 4K phat voi toc do 16Mbps chi su dung duoi 16% duong truyen 100Mbps. Dieu nay co nghia chat luong video on dinh bat ke dieu gi xay ra trong mang -- khong giat, khong giam chat luong, khong mat khung hinh.
Khoi dong lai nguon tu xa
Switch PoE co quan ly cho phep khoi dong lai tung camera tu xa tu bat ky dau. Neu camera bi treo hoac ngung phan hoi, ban co the khoi dong lai tu ban lam viec hoac dien thoai ma khong can treo thang hay den tan noi. Dieu nay tiet kiem rat nhieu thoi gian khi xu ly su co va bao tri.
Khong can thay pin
Camera PoE hoat dong 24/7/365 ma khong can bao tri nguon dien. Khong co pin de sac, thay the hay theo doi. Dieu nay dac biet quan trong cho camera gan o nhung noi kho tiep can -- duoi mai hien, tren cot hoac cao tren tuong ngoai troi, noi viec tiep can camera de thay pin se can xe nang hoac thang.
Uu diem cua WiFi chi tiet
Camera WiFi co nhung uu diem chinh dang lam cho chung tro thanh lua chon tot hon trong nhung tinh huong cu the. Dung loai bo WiFi chi vi PoE la tieu chuan chuyen nghiep.
Lap dat nhanh chong
Bo qua hoan toan viec di cap. Khong khoan tuong, khong keo cap qua tran, khong di ong bao ve ngoai troi. Gan camera, ket noi WiFi va ban da ghi hinh. Lap dat camera WiFi mat 15 phut moi camera, voi PoE se mat 1-2 gio sau khi tinh ca di cap, dau noi va kiem tra.
Bo tri linh hoat va de dang thay doi vi tri
Can di chuyen camera 10 met sang trai? Voi WiFi, thao ra va gan lai o vi tri moi. Voi PoE, ban phai keo cap moi hoac noi dai tuyen hien co. Camera WiFi ly tuong khi vi tri camera co the can dieu chinh trong qua trinh cai dat ban dau hoac khi nhu cau an ninh thay doi theo thoi gian.
Chi phi ban dau thap hon
Khong can cap Ethernet (0,50-1,50$ moi met), khong switch PoE (100-500$+), khong patch panel, khong thiet bi kiem tra cap. Doi voi he thong nha voi 4 camera, rieng cap va switch co the them 300-600$ vao lap dat PoE. WiFi loai bo hoan toan chi phi nay, du co the can bo khech dai WiFi (30-50$) neu tin hieu yeu.
Than thien voi nha thue: khong sua doi vinh vien
Tai bat dong san thue, ban khong the khoan lo tren tuong hay di cap ngoai troi. Camera WiFi voi gia do nam cham hoac dan dinh khong de lai vet khi don di. Model chay pin khong can o cam gan camera -- bao mat hoan toan khong xam lan ma ban mang theo khi het hop dong thue.
Vi tri xa va kho di cap
Garage rieng, nha chua do vuon, loi vao va nha phu la nhung noi ton kem va kho di cap tro lai toa nha chinh. Dao ranh chon cap ton 10-30$ moi met chi rieng nhan cong. Camera WiFi co tam nhin thang den router (hoac diem truy cap chuyen dung) giai quyet van de voi chi phi nho.
Khi nao nen chon PoE
PoE la lua chon dung khi do tin cay, hieu suat va gia tri dai han vuot troi chi phi lap dat ban dau cao hon. Nhung tinh huong nay uu tien ro rang camera co day.
Lap dat co dinh
Neu ban so huu bat dong san -- nha o, van phong, cua hang hay kho -- hay dau tu vao PoE. Ha tang cap co the ton tai 15-20 nam va vuot qua nhieu the he camera. Di cap Cat6 bay gio va ban se san sang cho mang 10Gbps khi camera the he tiep theo yeu cau.
He thong tu 4 camera tro len
Tren 3-4 camera, bang thong WiFi tro thanh nut that co chai that su. Bon camera 4MP phat dong thoi tieu thu khoang 24Mbps bang thong WiFi. Tam camera nang len 48Mbps, co the bao hoa hau het diem truy cap tieu dung va gay mat khung hinh hoac mat ket noi vao gio cao diem.
Ung dung an ninh quan trong
Ngan hang, kho hang, trung tam du lieu va bat ky moi truong nao ma gian doan ghi hinh la khong chap nhan duoc. 99,9% thoi gian hoat dong cua PoE va kha nang chong nhieu lam cho no tro thanh lua chon duy nhat co trach nhiem cho lap dat an ninh cao, noi tinh lien tuc cua bang chung la yeu cau phap ly hoac van hanh quan trong.
Ghi hinh lien tuc 24/7
He thong ghi hinh suot ngay dem can ket noi dam bao, khong gian doan. Camera WiFi bi offline du chi vai phut moi ngay co the bo lo su kien quan trong. PoE cung cap ket noi chuyen dung, on dinh ma ghi hinh lien tuc yeu cau, khong co bat ky gian doan nao.
He thong chat luong cao voi thoi gian luu tru dai
Neu he thong yeu cau luu tru 30+ ngay o chat luong cao (4MP tro len), ban can ket noi bang thong cao on dinh de tranh loi nen va mat khung hinh. Bang thong chuyen dung cua PoE dam bao moi khung hinh den NVR o chat luong day du.
Xay dung moi hoac cai tao
Khi tuong dang mo trong qua trinh xay dung hoac cai tao, chi phi bien cua viec di cap Ethernet la toi thieu. Di cap Cat6 den moi vi tri camera du kien khi tuong dang mo. Sau khi lap tam thach cao, di cap sau nay se dat hon 5-10 lan.
Giam sat khoang cach xa
Camera dat cach dau ghi 30+ met vuot qua pham vi WiFi dang tin cay qua hau het vat lieu xay dung. PoE ho tro tu nhien 100 met, va voi bo mo rong co the dat 200-300 met ma khong gap bat ky van de chat luong tin hieu nao.
Khi nao nen chon WiFi
Camera WiFi la lua chon thong minh khi tinh linh hoat, don gian hoac han che cua bat dong san lam cho viec di cap tro nen khong thuc te. Nhung tinh huong nay phat huy diem manh cua WiFi.
Bat dong san thue
Khi hop dong thue cam sua doi vinh vien, camera WiFi la lua chon kha thi duy nhat. Model chay pin voi gia do nam cham lap dat trong vai phut va khong de lai hu hong nao. Mang theo khi chuyen nha va lap dat lai o dia chi moi.
He thong nha nho (1-3 camera)
Cho camera tai cua truoc, cua sau va garage, WiFi hoan toan du. Ba camera khong lam qua tai mang WiFi, va khoan tiet kiem so voi di cap PoE qua nha da hoan thien co the dang ke. Camera WiFi hien dai tu cac thuong hieu uy tin du tin cay cho su dung tai nha.
Lap dat tam thoi
Cong truong xay dung, dia diem su kien, cua hang tam thoi va giam sat theo mua duoc huong loi tu tinh di dong cua WiFi. Trien khai camera nhanh cho thoi gian can thiet roi thu don. Di cap Ethernet cho du an xay dung 3 thang hiem khi hop ly ve kinh te.
Toa nha di san hoac kho di cap
Toa nha di san duoc bao ton, ket cau be tong nguyen khoi va toa nha co vat lieu chua amieng co the rat dat hoac bi han che phap ly ve viec di cap. WiFi hoan toan bo qua viec sua doi ket cau, bao ton toa nha dong thoi van cung cap phu song giam sat.
Lap dat DIY voi ngan sach han che
Neu ban tu lap dat va khong co kinh nghiem ve mang, camera WiFi cung cap nguong gia nhap thap hon nhieu. Khong can dung cu bam cap, khong patch panel, khong cau hinh switch. Hau het camera WiFi tieu dung huong dan cai dat qua ung dung dien thoai trong duoi 10 phut.
Bo sung cho he thong co day hien co
Da co he thong PoE nhung can camera o noi di cap khong thuc te? Camera WiFi co the lap day lo hong ma khong mat chi phi tuyen cap moi. Vi du dien hinh bao gom garage rieng, camera tai cong hoac camera giam sat tre em trong nha.
Phuong phap ket hop
Trong thuc te, cac he thong CCTV tot nhat thuong ket hop ca hai cong nghe. Phuong phap ket hop su dung PoE cho phan cot loi camera co dinh, quan trong, dong thoi trien khai camera WiFi tai nhung vi tri ma di cap khong thuc te hoac qua ton kem.
Chien luoc nay mang lai do tin cay cua camera co day o noi quan trong nhat, voi su linh hoat cua khong day o noi can thiet. Nhieu NVR hien dai ho tro ca camera PoE va WiFi trong mot he thong, lam cho viec quan ly tro nen lien mach.
PoE cho camera quan trong
Loi vao chinh, quay thu ngan, phong may chu, camera nhin ra bai do xe va bat ky vi tri nao ma ghi hinh 24/7 khong gian doan la bat buoc. Nhung camera nay tao thanh xu song cua he thong an ninh va khong bao gio duoc phep offline.
WiFi cho camera bo sung
Phu song bo sung tai nhung noi kho tiep can: vuon sau, nha de xe rieng, cong ben hoac phong trong nha ma viec di cap se can thiet pha vo ket cau. Nhung camera nay tang chieu sau phu song nhung khong phai la nguon bang chung chinh.
Phan doan mang
De hieu suat va bao mat tot nhat, tao VLAN chuyen dung cho luu luong camera. Dieu nay cach ly du lieu giam sat khoi luu luong mang chung, ngan chan truy cap camera tu thiet bi trai phep va dam bao bang thong kha dung khi can. Hau het switch co quan ly ho tro VLAN ngay tu dau.
Vi du: he thong 8 camera
Trien khai ket hop dien hinh co the bao gom 5 camera PoE (loi vao chinh, loi vao sau, bai do xe, quay thu ngan, kho) cong 3 camera WiFi (cong ben, garage rieng, tam nhin vuon). Camera PoE dam bao phu song lien tuc cac khu vuc quan trong, trong khi camera WiFi mo rong phu song den nhung vi tri ma di cap se ton hon ban than camera.