테스트 환경 검증

Wi-Fi 모듈을 측정한 결과를 정리하였다.
현재 검토 중인 Chipset은 Broadcom 과 Realtek 이다. Chip Spec 는 다음과 같다.

Chipset	BCM43362
802.11 Spec	b/g/n 2.4GHz
Interface	SDIO
Antenna	1 by 1

쉴드룸 상황과 일반 사무실 환경이 어느 정도 차이가 나는지 측정했다. 일반적인 throughput 이 아닌 신호 세기와 감도를 확인하기 위해 진행했다.
다음의 몇가지 상황에 따라 측정했다.
참고로 Built-in Wi-Fi 는 802.11b/g 만 지원하고, IPTIME Wi-Fi 는 802.11b/g/n 을 지원하기 때문에 각각 공유기 설정을 'g/n 모드' 그리고 'n only' 로 설정했다.

root@debian:~# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
 
root@debian:~# iwlist wlan0 scan
wlan0     No scan results

root@debian:~# iwconfig ra0 
ra0       Ralink STA  ESSID:""  Nickname:"RT2870STA"
          Mode:Auto  Frequency=2.412 GHz  Bit Rate=1 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=10/100  Signal level:0 dBm  Noise level:0 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~# iwlist ra0 scan
ra0       No scan results

root@debian:~# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:off/any  
          Mode:Managed  Access Point: Not-Associated   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
 
root@debian:~# iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: 00:26:66:AA:E7:B4
                    Channel:9
                    Frequency:2.452 GHz (Channel 9)
                    Quality=39/70  Signal level=-71 dBm  
                    Encryption key:off
                    ESSID:"ttt"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=000000000b3c9173
                    Extra: Last beacon: 112ms ago 
                    IE: Unknown: 0003747474
                    IE: Unknown: 010882848B960C121824
                    IE: Unknown: 030109
                    IE: Unknown: 2A0100
                    IE: Unknown: 32043048606C
                    IE: Unknown: 2D1A6E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D1609050000000000000000000000000000000000000000
                    IE: Unknown: DD180050F2020101000003A4000027A4000042435E0062322F00
                    IE: Unknown: DD9E0050F204104A0001101044000102103B0001031047001063041253101920061228AABBCCDDEEFF1021001B5265616C74656B2053656D69636F6E647563746F7220436F72702E1023000752544C387878781024000D45562D323030392D30322D30361042000F3132333435363738393031323334371054000800060050F2040001101100135265616C74656B20576972656C657373204150100800020086
                    IE: Unknown: DD1E00904C336E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: DD1A00904C3409050000000000000000000000000000000000000000
                    IE: Unknown: DD0600E04C020160

root@debian:~# iwconfig ra0 
ra0       Ralink STA  ESSID:""  Nickname:"RT2870STA"
          Mode:Auto  Frequency=2.412 GHz  Bit Rate=1 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=10/100  Signal level:0 dBm  Noise level:0 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~# iwlist ra0 scan
ra0       Scan completed :
          Cell 01 - Address: 00:26:66:AA:E7:B4
                    Protocol:802.11b/g/n
                    ESSID:"ttt"
                    Mode:Managed
                    Frequency:2.452 GHz (Channel 9)
                    Quality=100/100  Signal level=-27 dBm  Noise level=-92 dBm 
                    Encryption key:off
                    Bit Rates:54 Mb/s
                    IE: Unknown: DD0E0050F204104A0001101044000102

root@debian:/# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"ttt"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=1 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=70/70  Signal level=-35 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:/# iwlist wlan0 scan
wlan0     Scan completed :
          Cell 01 - Address: 00:26:66:AA:E7:B4
                    Channel:1
                    Frequency:2.412 GHz (Channel 1)
                    Quality=70/70  Signal level=-37 dBm  
                    Encryption key:off
                    ESSID:"ttt"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=0000000001e428b2
                    Extra: Last beacon: 8ms ago 
                    IE: Unknown: 0003747474
                    IE: Unknown: 010882848B960C121824
                    IE: Unknown: 030101
                    IE: Unknown: 2A0100
                    IE: Unknown: 32043048606C
                    IE: Unknown: 2D1A6E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D1601050300000000000000000000000000000000000000
                    IE: Unknown: DD180050F2020101000003A4000027A4000042435E0062322F00
                    IE: Unknown: DD9E0050F204104A0001101044000102103B0001031047001063041253101920061228AABBCCDDEEFF1021001B5265616C74656B2053656D69636F6E647563746F7220436F72702E1023000752544C387878781024000D45562D323030392D30322D30361042000F3132333435363738393031323334371054000800060050F2040001101100135265616C74656B20576972656C657373204150100800020086
                    IE: Unknown: DD1E00904C336E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: DD1A00904C3401050300000000000000000000000000000000000000
                    IE: Unknown: DD0600E04C020160
 
root@debian:/# 
root@debian:/# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"ttt"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=1 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=70/70  Signal level=-20 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

root@debian:/# iwconfig ra0 essid ttt 
root@debian:/# dhclient ra0 
root@debian:/# iwconfig ra0 
ra0       Ralink STA  ESSID:"ttt"  Nickname:"RT2870STA"
          Mode:Managed  Frequency=2.452 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=135 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=100/100  Signal level:-25 dBm  Noise level:-25 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:/# iwlist ra0 scan
ra0       Scan completed :
          Cell 01 - Address: 00:26:66:AA:E7:B4
                    Protocol:802.11b/g/n
                    ESSID:"ttt"
                    Mode:Managed
                    Frequency:2.452 GHz (Channel 9)
                    Quality=100/100  Signal level=-27 dBm  Noise level=-92 dBm 
                    Encryption key:off
                    Bit Rates:54 Mb/s
                    IE: Unknown: DD0E0050F204104A0001101044000102
 
root@debian:/# 
root@debian:/# iwconfig ra0 
ra0       Ralink STA  ESSID:"ttt"  Nickname:"RT2870STA"
          Mode:Managed  Frequency=2.452 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=135 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=100/100  Signal level:-20 dBm  Noise level:-50 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

항목	접속 전	접속 후
TX Power	20	20
Link Quality	없음	70/70
Signal level	없음	-35 ~ -20 dBm
Bit Rate	없음	1 Mb/s

항목	접속 전	접속 후
TX Power	없음	없음
Link Quality	10/100	100/100
Signal level	0 dBm	-25 ~ -20 dBm
Bit Rate	1 Mb/s	135 Mb/s
Noise level	0 dBm	-25 ~ -50 dBm

같은 테스트를 이번에는 사무실 환경에서 진행했다.

# iwlist wlan0 scan
          Cell 20 - Address: 00:26:66:AA:E7:B4
                    Channel:13
                    Frequency:2.472 GHz (Channel 13)
                    Quality=57/70  Signal level=-53 dBm
                    Encryption key:off
                    ESSID:"ttt"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=00000000907ef15d
                    Extra: Last beacon: 156ms ago
                    IE: Unknown: 0003747474
                    IE: Unknown: 010882848B960C121824
                    IE: Unknown: 03010D
                    IE: Unknown: 2A0100
                    IE: Unknown: 32043048606C
                    IE: Unknown: 2D1A6E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: 3D160D070000000000000000000000000000000000000000
                    IE: Unknown: DD180050F2020101000003A4000027A4000042435E0062322F00
                    IE: Unknown: DD9E0050F204104A0001101044000102103B0001031047001063041253101920061228AABBCCDDEEFF1021001B5265616C74656B2053656D69636F6E647563746F7220436F72702E1023000752544C387878781024000D45562D323030392D30322D30361042000F3132333435363738393031323334371054000800060050F2040001101100135265616C74656B20576972656C657373204150100800020086
                    IE: Unknown: DD1E00904C336E181AFFFF000000000000000000000000000000000000000000
                    IE: Unknown: DD1A00904C340D070000000000000000000000000000000000000000
                    IE: Unknown: DD0600E04C020160
 
 
# iwconfig wlan0 essid ttt
# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"ttt"  
          Mode:Managed  Frequency:2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=54 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=65/70  Signal level=-45 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~/wifi_company# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"ttt"  
          Mode:Managed  Frequency:2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=54 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=66/70  Signal level=-44 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~/wifi_company# iwconfig wlan0
wlan0     IEEE 802.11bg  ESSID:"ttt"  
          Mode:Managed  Frequency:2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=54 Mb/s   Tx-Power=20 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=67/70  Signal level=-43 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

# iwconfig ra0 
ra0       Ralink STA  ESSID:""  Nickname:"RT2870STA"
          Mode:Auto  Frequency=2.412 GHz  Bit Rate=1 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=10/100  Signal level:0 dBm  Noise level:0 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
# iwlist ra0 scan
          Cell 03 - Address: 00:26:66:AA:E7:B4
                    Protocol:802.11b/g/n
                    ESSID:"ttt"
                    Mode:Managed
                    Frequency:2.472 GHz (Channel 13) 
                    Quality=23/100  Signal level=-81 dBm  Noise level=-86 dBm 
                    Encryption key:off
                    Bit Rates:54 Mb/s
                    IE: Unknown: DD0E0050F204104A0001101044000102
 
# iwconfig ra0 essid ttt
oot@debian:~/wifi_company# iwconfig ra0 
ra0       Ralink STA  ESSID:"ttt"  Nickname:"RT2870STA"
          Mode:Managed  Frequency=2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=135 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=100/100  Signal level:-54 dBm  Noise level:-72 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~/wifi_company# iwconfig ra0 
ra0       Ralink STA  ESSID:"ttt"  Nickname:"RT2870STA"
          Mode:Managed  Frequency=2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=135 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=100/100  Signal level:-54 dBm  Noise level:-74 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
 
root@debian:~/wifi_company# iwconfig ra0 
ra0       Ralink STA  ESSID:"ttt"  Nickname:"RT2870STA"
          Mode:Managed  Frequency=2.472 GHz  Access Point: 00:26:66:AA:E7:B4   
          Bit Rate=135 Mb/s   
          RTS thr:off   Fragment thr:off
          Encryption key:off
          Link Quality=88/100  Signal level:-52 dBm  Noise level:-72 dBm 
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

항목	접속 전	접속 후
TX Power	20	20
Link Quality	없음	65~67/70
Signal level	없음	-43 ~ -45 dBm
Bit Rate	없음	54 Mb/s

항목	접속 전	접속 후
TX Power	없음	없음
Link Quality	10/100	88~100/100
Signal level	0 dBm	-52 ~ -54 dBm
Bit Rate	1 Mb/s	135 Mb/s
Noise level	0 dBm	-72 ~ -74 dBm

IPTIME 에서 나온 USB 타입의 WiFi 동글이다. 칩은 ralink5370 을 사용한다.

먼저 IPTIME 홈페이지에서 해당 리눅스 드라이버를 다운로드 한다.
압축을 풀고, make 를 실행하면 되는데, 여기서 선행되어야 할 것이 있다.

#cd 2011_0719_RT3070_RT3370_RT5370_RT5372_Linux_STA_V2.5.0.3_DPO
#mkdir -p /etc/Wireless/RT2870STA
#cp RT2870STA.dat /etc/Wireless/RT2870STA/
#insmod rt5370sta.ko
#ifconfig ra0 up

만일 ra0 인터페이스가 올라오지 않는다면, dmesg 를 통해 커널메세지를 확인하자.

#cp rt5370sta.ko /lib/modules/3.5.0-24-generic/kernel/drivers/net/wireless
#depmod -a
#vi /etc/modules

아래와 같이 추가한다.

rt5370sta

지금까지 두번에 걸쳐 성능 테스트를 했다.
첫번째는 일반 사무실 환경에서 했고, 두번째는 쉴드룸 환경에서 진행했다. 먼저 BCM 으로부터 받은 사전 성능 데이터를 참고했다. bcm43362_throughput.pdf

일반 사무실 환경 성능 테스트 wifi_result_nomal.odt
쉴드룸 환경 성능 테스트 wifi_result_shelidrom.odt

BCM 자료와 비교해볼때, 쉴드룸 환경에서 RX 가 절반 정도밖에 나오지 않고 있다. 개선되어야 할 부분이다.

최소 기준 throughput 은 얼마로 할 것인가? 현재 유선랜에서의 throughput 은 얼마인가? 저장되는 스트림의 data rate 은 얼마인가?
몇 개까지 지원할 것인가?
Wi-Fi 인증을 받을 것인가?
어떤 기능까지 지원할 것인가?
AP or Soft AP 기능을 사용할 것인가?

IP 카메라와 NVR 간에 성능 측정(Throughput, CPU Usage)

WIFI High Speed Mode 를 비활성화(disable)한 펌웨어로 무선 성능을 측정한 결과는 다음과 같다. 수정사항은 dm368_사용하기_개정판 를 참조한다.

쉴드룸(8층)
AP 공유기 : IPTIME N804, 암호없음, 802.11 b/g/n 으로 설정
Carmera App 를 실행하지 않고, 커널부팅 후 바로 Throughput 측정함
TX/RX 각각 300초(5분) 동안 측정함

TX(CPU Usage)	RX(CPU Usage)	비고
16.5(60%)	11.1(40%)	TX(최고 : 16.8 Mbps, 최저 : 15.7 Mbps), RX(최고 : 13.5 Mbps, 최저 : 2.22 Mbps)

측정 결과, TX 의 경우 기존과 동일한 결과를 나타냈으며 RX 의 경우, 큰 편차가 발생하나, 발생 빈도가 기존에 비해 줄었다.

OQC 시료를 사용하여 무선 성능 측정을 하였다. 기존대로 SDIO Clock 을 50 MHz 로 설정했을 때, 통신 도중 죽거나, 드라이버가 다운되는 문제가 있어 Clock 을 각각, 5/10/15 MHz 로 변경하여 측정하였다.

TX(CPU Usage)	RX(CPU Usage)	비고
17.2(80%)	13.0(55%)

TX(CPU Usage)	RX(CPU Usage)	비고
13.8(55%)	12.1(30%)

TX(CPU Usage)	RX(CPU Usage)	비고
19.9(98%)	16.8(65%)

TX(CPU Usage)	RX(CPU Usage)	비고
18.4(70%)	14.3(35~40%)

TX(CPU Usage)	RX(CPU Usage)	비고
15.0(70%)	13.8(35~40%)

TX(CPU Usage)	RX(CPU Usage)	비고
9.74(35~40%)	9.34(35~40%)

성능 측정 결과를 wifi_dongle_realtek_0528.doc 파일에 작성했다.

MMC Clock 을 조절 했을 때, 다음과 같이 결과가 나왔다. drivers/mmc/core/sdio.c 파일을 다음과 같이 수정했다.

static unsigned mmc_sdio_get_max_clock(struct mmc_card *card)
{
    unsigned max_dtr;
 
    if (mmc_card_highspeed(card)) {
        /*  
         * The SDIO specification doesn't mention how
         * the CIS transfer speed register relates to
         * high-speed, but it seems that 50 MHz is
         * mandatory.
         */
//      max_dtr = 50000000;
          max_dtr = 35000000;       // wjkim
//        max_dtr = 25000000;       // wjkim
//        max_dtr = 15000000;       // wjkim
 
            printk("max_dtr ####################### %d \n", max_dtr);
 
    } else {
        max_dtr = card->cis.max_dtr;
    }   
 
    if (card->type == MMC_TYPE_SD_COMBO)
        max_dtr = min(max_dtr, mmc_sd_get_max_clock(card));
 
    return max_dtr;
}

TX(CPU Usage)	RX(CPU Usage)	비고
24.7(95~98%)	13.4(15%)	RX 측정 시, 도중 끊어지는 문제 발생함

TX(CPU Usage)	RX(CPU Usage)	비고
22.7(90%)	15.7(30%)

TX(CPU Usage)	RX(CPU Usage)	비고
19.1(70%)	15.6(35~40%)

TX(CPU Usage)	RX(CPU Usage)	비고
19.4(70%)	14.7(35~40%)

측정 결과, 35 MHz 에서 가장 안정적이고도, 높은 성능을 나타냈다. 따라서 35 MHz 로 설정했다.

테스트 환경 검증

쉴드룸

Wi-Fi 만 있을 경우

Built-in Wi-Fi

IPTIME Wi-Fi

Wi-Fi 와 AP 가 있는 경우(접속안함)

Built-in Wi-Fi

IPTIME Wi-Fi

Wi-Fi 가 AP 에 접속한 경우

Built-in Wi-Fi

IPTIME Wi-Fi

실험 결과

Built-in Wi-Fi

IPTIME Wi-Fi

사무실 환경

Built-in Wi-Fi

IPTIME Wi-Fi

실험 결과

Built-in Wi-Fi

IPTIME Wi-Fi

IPTIME N150UA

드라이버 포팅하기

부팅시 자동으로 모듈 로딩하기

Broadcom 43362

현재 상황

Realtek

고려해야할 사항

확인해 볼 사항

성능 측정 결과

무선 카메라(2013.09.09)

무선 카메라(2013.07.25)

50 MHz 설정

1번 시료

2번 시료

3번 시료

15 MHz 설정

10 MHz 설정

5 MHz 설정

지능형 카메라(2013.05.28)

무선 카메라(2013.05.14)

50 MHz 설정

35 MHz 설정

25 MHz 설정

15 MHz 설정