Could not download sdk.aar (com.estimote:sdk:0.9.4)

I am creating a new android app with Estimote beacons, and as per the estimote guidelines, I tried including estimote library in following way,

dependencies {
compile fileTree(dir: ‘libs’, include: [‘*.jar’])
testCompile ‘junit:junit:4.12’
compile ‘com.estimote:sdk:0.9.4@aar’
compile ‘com.android.support:appcompat-v7:21.0.3’
compile ‘com.google.android.gms:play-services:8.1.0’
compile ‘com.android.support:recyclerview-v7:21.0.3’
compile ‘com.android.support:cardview-v7:21.0.3’
}

and android studio came up with following message,

Error:A problem occurred configuring project ‘:app’.

Could not download sdk.aar (com.estimote:sdk:0.9.4)
Could not get resource ‘https://jcenter.bintray.com/com/estimote/sdk/0.9.4/sdk-0.9.4.aar’.
Could not GET ‘https://jcenter.bintray.com/com/estimote/sdk/0.9.4/sdk-0.9.4.aar’.
peer not authenticated

I think there might be something wrong with your Internet connection. If you visit https://jcenter.bintray.com/com/estimote/sdk/0.9.4/sdk-0.9.4.aar in your browser, does it start downloading the AAR file?